{"id":1758,"date":"2021-09-08T13:07:29","date_gmt":"2021-09-08T05:07:29","guid":{"rendered":"http:\/\/www.shuizilong.com\/house\/?p=1758"},"modified":"2021-09-08T13:35:01","modified_gmt":"2021-09-08T05:35:01","slug":"spoj-cot3","status":"publish","type":"post","link":"https:\/\/www.shuizilong.com\/house\/archives\/spoj-cot3\/","title":{"rendered":"SPOJ COT3"},"content":{"rendered":"<p><a href=\"https:\/\/www.spoj.com\/problems\/COT3\/\">https:\/\/www.spoj.com\/problems\/COT3\/<\/a><br \/>\n<a href=\"https:\/\/blog.csdn.net\/huzecong\/article\/details\/9142121\">https:\/\/blog.csdn.net\/huzecong\/article\/details\/9142121<\/a><br \/>\n<a href=\"https:\/\/my.oschina.net\/u\/4321213\/blog\/3694105\">https:\/\/my.oschina.net\/u\/4321213\/blog\/3694105<\/a><\/p>\n<p>\u975e\u5e38 nice \u7684\u9898\u76ee&#8230; \u540c\u65f6\u8003\u5bdf\u7ec4\u5408\u535a\u5f08\u548c\u7ebf\u6bb5\u6811\u5408\u5e76\u3002\u3002\u3002<br \/>\n\u4e0d\u59a8\u5148\u8003\u8651\u7b80\u5355\u7684\u95ee\u9898\uff0c\u5982\u4f55\u8f93\u51fa\u7b2c\u4e00\u6b65\u7684\u65b9\u6848\u3002<br \/>\n\u6211\u4eec\u679a\u4e3e\u7b2c\u4e00\u6b65\u843d\u5728\u54ea\u91cc\uff0c\u90a3\u4e48\u5f62\u6210\u7684\u9ed1\u94fe\u4f1a\u628a\u539f\u6811\u5212\u5206\u4e3a\u82e5\u5e72\u5b50\u6811\uff0c\u6bcf\u7ec4\u5b50\u6811\u76f8\u4e92\u72ec\u7acb\uff0c\u4e8e\u662f\u53d8\u6210\u6e38\u620f\u7684\u548c\uff0c<br \/>\n\u6839\u636e SG \u5b9a\u7406\uff0c\u6211\u4eec\u53ea\u8981\u80fd\u6c42\u51fa\u6bcf\u4e2a\u8282\u70b9\u4e3a\u6839\u7684 sg \u503c\u5373\u53ef\u3002<\/p>\n<pre class=\"brush: cpp; light: false; title: ; toolbar: true; notranslate\" title=\"\">\r\nvoid gao(int u = 1, int p = -1, int SG = 0) { \/\/ \u9012\u5f52\u8fdb\u6765\u7684 SG \u8868\u793a\u5b50\u6811\u5916\u7684\u6e38\u620f\r\n    for (auto v: adj&#x5B;u]) if (v != p) SG ^= sg&#x5B;v]; \/\/ \u518d xor \u4e0a\u5b50\u6811\u5185\u7684\u6e38\u620f\r\n    if (!col&#x5B;u] &amp;&amp; !SG) Z.PB(u);\r\n    for (auto v: adj&#x5B;u]) if (v != p) gao(v, u, SG^sg&#x5B;v]);\r\n}\r\n<\/pre>\n<p>\u518d\u8003\u8651\u5982\u4f55\u6c42\u4ee5 u \u4e3a\u6839\u7684\u5b50\u6811\u7684 sg \u503c\uff0c\u6211\u4eec\u8003\u8651\u7b2c\u4e00\u6b65\u600e\u4e48\u8d70\uff0c\u5e76\u4e14\u7ef4\u62a4\u6240\u6709\u80fd\u8f6c\u79fb\u5230\u7684 sg \u503c\u7684\u96c6\u5408\u3002<br \/>\n\u8ba8\u8bba\u8282\u70b9 u \u7684\u989c\u8272\u3002<br \/>\n\u5982\u679c\u662f\u9ed1\u8272\uff0c\u6211\u4eec\u8fd8\u662f\u679a\u4e3e\u7b2c\u4e00\u6b65\u843d\u5728\u5b50\u6811\u4e2d\u54ea\u4e00\u4e2a\u8282\u70b9\u91cc\uff0c\u90a3\u4e48\u548c\u4e0a\u9762\u7684\u60c5\u51b5\u4e00\u6837\uff0c\u4e5f\u662f\u62c6\u5206\u6210\u4e86\u82e5\u5e72\u6e38\u620f\u7684\u548c\u3002<br \/>\n\u5982\u679c\u662f\u767d\u8272\uff0c\u90a3\u4e48\u591a\u4e00\u79cd\u64cd\u4f5c\uff0c\u628a\u8fd9\u4e2a sg \u4e5f\u4e22\u5230\u96c6\u5408\u91cc\u3002\uff08\u5bf9\u5e94\u4e0b\u9762 !col[u] \u7684\u60c5\u51b5\uff09<br \/>\n\u6700\u540e\u628a\u6240\u6709 sg \u503c\u7684\u96c6\u5408 mex \u4e00\u4e0b\u5373\u53ef\u3002<br \/>\n\u8fd9\u6837\u66b4\u529b O(n2) \u7684\u7b97\u6cd5\u5c31\u6709\u4e86\u3002<\/p>\n<pre class=\"brush: cpp; light: false; title: ; toolbar: true; notranslate\" title=\"\">\r\nvoid dfs(int u = 1, int p = -1) {\r\n    int s = 0;\r\n    for (auto v: adj&#x5B;u]) if (v != p) {\r\n        dfs(v, u); s ^= sg&#x5B;v];\r\n    }\r\n    if (!col&#x5B;u]) Init(rt&#x5B;u], LV, s);\r\n    for (auto v: adj&#x5B;u]) if (v != p) {\r\n        put_xor(rt&#x5B;v], LV, s ^ sg&#x5B;v]);\r\n        rt&#x5B;u] = Merge(rt&#x5B;u], rt&#x5B;v]);\r\n    }\r\n    sg&#x5B;u] = Mex(rt&#x5B;u], LV);\r\n}\r\n<\/pre>\n<p>\u8003\u8651\u4f18\u5316\uff0c\u6211\u4eec\u53ef\u4ee5\u7528 01-Trie \u53bb\u7ef4\u62a4 sg \u503c\u7684\u96c6\u5408\uff0c\u90a3\u4e48\u4e0a\u9762\u7684\u679a\u4e3e\u8fc7\u7a0b\u5c31\u4e0d\u9700\u8981\u8fdb\u5165\u5b50\u6811\u679a\u4e3e\u3002<br \/>\n\u800c\u53ea\u8981\u5206\u6210 v \u8282\u70b9\u4e2d\u7684 sg \u96c6\u5408\uff0c\u548c v \u8282\u70b9\u5916\u7684\u7ec4\u6210\u7684 sg \u4e24\u4e2a\u72b6\u6001\u5373\u53ef\uff0c\u800c\u8fd9\u4e2a\u76f8\u5f53\u4e8e\u7ed9\u6574\u4e2a\u96c6\u5408\u6253 xor tag \u7136\u540e\u518d\u5408\u5e76\u3002<br \/>\n\u800c 01-Trie \u548c\u7ebf\u6bb5\u6811\u7ed3\u6784\u51e0\u4e4e\u4e00\u6837\uff0c\u7a0d\u5fae\u6539\u6539\u5373\u53ef\u3002<\/p>\n<p>\u590d\u6742\u5ea6 O(nlogn)\u3002<\/p>\n<pre class=\"brush: cpp; light: false; title: ; toolbar: true; notranslate\" title=\"\">\r\n\/*\r\n    This code has been written by MinakoKojima, feel free to ask me question. Blog: https:\/\/www.shuizilong.com\/house\r\n    Template Date: 2015.10.12\r\n    Note: ...\r\n*\/\r\n\r\n#pragma comment(linker, &quot;\/STACK:36777216&quot;)\r\n\/\/#pragma GCC optimize (&quot;O2&quot;)\r\n#define LOCAL\r\n#include &lt;functional&gt;\r\n#include &lt;algorithm&gt;\r\n#include &lt;iostream&gt;\r\n#include &lt;fstream&gt;\r\n#include &lt;sstream&gt;\r\n#include &lt;iomanip&gt;\r\n#include &lt;numeric&gt;\r\n#include &lt;cstring&gt;\r\n#include &lt;climits&gt;\r\n#include &lt;cassert&gt;\r\n#include &lt;complex&gt;\r\n#include &lt;cstdio&gt;\r\n#include &lt;string&gt;\r\n#include &lt;vector&gt;\r\n#include &lt;bitset&gt;\r\n#include &lt;queue&gt;\r\n#include &lt;stack&gt;\r\n#include &lt;cmath&gt;\r\n#include &lt;ctime&gt;\r\n#include &lt;list&gt;\r\n#include &lt;set&gt;\r\n#include &lt;map&gt;\r\n\r\n\/\/#include &lt;tr1\/unordered_set&gt;\r\n\/\/#include &lt;tr1\/unordered_map&gt;\r\n\/\/#include &lt;array&gt;\r\n\r\nusing namespace std;\r\n\r\n#define REP(i, n) for (int i=0;i&lt;n;++i)\r\n#define FOR(i, a, b) for (int i=a;i&lt;b;++i)\r\n#define DWN(i, b, a) for (int i=b-1;i&gt;=a;--i)\r\n#define REP_1(i, n) for (int i=1;i&lt;=n;++i)\r\n#define FOR_1(i, a, b) for (int i=a;i&lt;=b;++i)\r\n#define DWN_1(i, b, a) for (int i=b;i&gt;=a;--i)\r\n#define REP_C(i, n) for (int n____=n,i=0;i&lt;n____;++i)\r\n#define FOR_C(i, a, b) for (int b____=b,i=a;i&lt;b____;++i)\r\n#define DWN_C(i, b, a) for (int a____=a,i=b-1;i&gt;=a____;--i)\r\n#define REP_N(i, n) for (i=0;i&lt;n;++i)\r\n#define FOR_N(i, a, b) for (i=a;i&lt;b;++i)\r\n#define DWN_N(i, b, a) for (i=b-1;i&gt;=a;--i)\r\n#define REP_1_C(i, n) for (int n____=n,i=1;i&lt;=n____;++i)\r\n#define FOR_1_C(i, a, b) for (int b____=b,i=a;i&lt;=b____;++i)\r\n#define DWN_1_C(i, b, a) for (int a____=a,i=b;i&gt;=a____;--i)\r\n#define REP_1_N(i, n) for (i=1;i&lt;=n;++i)\r\n#define FOR_1_N(i, a, b) for (i=a;i&lt;=b;++i)\r\n#define DWN_1_N(i, b, a) for (i=b;i&gt;=a;--i)\r\n#define REP_C_N(i, n) for (int n____=(i=0,n);i&lt;n____;++i)\r\n#define FOR_C_N(i, a, b) for (int b____=(i=0,b);i&lt;b____;++i)\r\n#define DWN_C_N(i, b, a) for (int a____=(i=b-1,a);i&gt;=a____;--i)\r\n#define REP_1_C_N(i, n) for (int n____=(i=1,n);i&lt;=n____;++i)\r\n#define FOR_1_C_N(i, a, b) for (int b____=(i=a,b);i&lt;=b____;++i)\r\n#define DWN_1_C_N(i, b, a) for (int a____=(i=b,a);i&gt;=a____;--i)\r\n\r\n#define ECH(it, A) for (__typeof((A).begin()) it=(A).begin(); it != (A).end(); ++it)\r\n#define rECH(it, A) for (__typeof((A).rbegin()) it=(A).rbegin(); it != (A).rend(); ++it)\r\n#define REP_S(i, str) for (char*i=str;*i;++i)\r\n#define REP_L(i, hd, suc) for (int i=hd;i;i=suc&#x5B;i])\r\n#define REP_G(i, u) REP_L(i,hd&#x5B;u],suc)\r\n#define REP_SS(x, s) for (int x=s;x;x=(x-1)&amp;s)\r\n#define DO(n) for ( int ____n = n; ____n--&gt;0; )\r\n#define REP_2(i, j, n, m) REP(i, n) REP(j, m)\r\n#define REP_2_1(i, j, n, m) REP_1(i, n) REP_1(j, m)\r\n#define REP_3(i, j, k, n, m, l) REP(i, n) REP(j, m) REP(k, l)\r\n#define REP_3_1(i, j, k, n, m, l) REP_1(i, n) REP_1(j, m) REP_1(k, l)\r\n#define REP_4(i, j, k, ii, n, m, l, nn) REP(i, n) REP(j, m) REP(k, l) REP(ii, nn)\r\n#define REP_4_1(i, j, k, ii, n, m, l, nn) REP_1(i, n) REP_1(j, m) REP_1(k, l) REP_1(ii, nn)\r\n\r\n#define ALL(A) A.begin(), A.end()\r\n#define LLA(A) A.rbegin(), A.rend()\r\n#define CPY(A, B) memcpy(A, B, sizeof(A))\r\n#define INS(A, P, B) A.insert(A.begin() + P, B)\r\n#define ERS(A, P) A.erase(A.begin() + P)\r\n#define LBD(A, x) (lower_bound(ALL(A), x) - A.begin())\r\n#define UBD(A, x) (upper_bound(ALL(A), x) - A.begin())\r\n#define CTN(T, x) (T.find(x) != T.end())\r\n#define SZ(A) int((A).size())\r\n#define PB push_back\r\n#define MP(A, B) make_pair(A, B)\r\n#define PTT pair&lt;T, T&gt;\r\n#define Ts *this\r\n#define rTs return Ts\r\n#define fi first\r\n#define se second\r\n#define re real()\r\n#define im imag()\r\n\r\n#define Rush for(int ____T=RD(); ____T--;)\r\n#define Display(A, n, m) {                      \\\r\n  REP(i, n){\t\t                            \\\r\n        REP(j, m-1) cout &lt;&lt; A&#x5B;i]&#x5B;j] &lt;&lt; &quot; &quot;;     \\\r\n        cout &lt;&lt; A&#x5B;i]&#x5B;m-1] &lt;&lt; endl;\t\t        \\\r\n\t}\t\t\t\t\t\t                    \\\r\n}\r\n#define Display_1(A, n, m) {                    \\\r\n\tREP_1(i, n){\t\t                        \\\r\n        REP_1(j, m-1) cout &lt;&lt; A&#x5B;i]&#x5B;j] &lt;&lt; &quot; &quot;;   \\\r\n        cout &lt;&lt; A&#x5B;i]&#x5B;m] &lt;&lt; endl;\t\t        \\\r\n\t}\t\t\t\t\t\t                    \\\r\n}\r\n\r\ntypedef long long LL;\r\n\/\/typedef long double DB;\r\ntypedef double DB;\r\ntypedef unsigned uint;\r\ntypedef unsigned long long uLL;\r\n\r\ntypedef vector&lt;int&gt; VI;\r\ntypedef vector&lt;char&gt; VC;\r\ntypedef vector&lt;string&gt; VS;\r\ntypedef vector&lt;LL&gt; VL;\r\ntypedef vector&lt;DB&gt; VF;\r\ntypedef set&lt;int&gt; SI;\r\ntypedef set&lt;string&gt; SS;\r\ntypedef map&lt;int, int&gt; MII;\r\ntypedef map&lt;string, int&gt; MSI;\r\ntypedef pair&lt;int, int&gt; PII;\r\ntypedef pair&lt;LL, LL&gt; PLL;\r\ntypedef vector&lt;PII&gt; VII;\r\ntypedef vector&lt;VI&gt; VVI;\r\ntypedef vector&lt;VII&gt; VVII;\r\n\r\ntemplate&lt;class T&gt; inline T&amp; RD(T &amp;);\r\ntemplate&lt;class T&gt; inline void OT(const T &amp;);\r\n\/\/inline int RD(){int x; return RD(x);}\r\ninline LL RD(){LL x; return RD(x);}\r\ninline DB&amp; RF(DB &amp;);\r\ninline DB RF(){DB x; return RF(x);}\r\ninline char* RS(char *s);\r\ninline char&amp; RC(char &amp;c);\r\ninline char RC();\r\ninline char&amp; RC(char &amp;c){scanf(&quot; %c&quot;, &amp;c); return c;}\r\ninline char RC(){char c; return RC(c);}\r\n\/\/inline char&amp; RC(char &amp;c){c = getchar(); return c;}\r\n\/\/inline char RC(){return getchar();}\r\n\r\ntemplate&lt;class T&gt; inline T&amp; RDD(T &amp;);\r\ninline LL RDD(){LL x; return RDD(x);}\r\n\r\ntemplate&lt;class T0, class T1&gt; inline T0&amp; RD(T0 &amp;x0, T1 &amp;x1){RD(x0), RD(x1); return x0;}\r\ntemplate&lt;class T0, class T1, class T2&gt; inline T0&amp; RD(T0 &amp;x0, T1 &amp;x1, T2 &amp;x2){RD(x0), RD(x1), RD(x2); return x0;}\r\ntemplate&lt;class T0, class T1, class T2, class T3&gt; inline T0&amp; RD(T0 &amp;x0, T1 &amp;x1, T2 &amp;x2, T3 &amp;x3){RD(x0), RD(x1), RD(x2), RD(x3); return x0;}\r\ntemplate&lt;class T0, class T1, class T2, class T3, class T4&gt; inline T0&amp; RD(T0 &amp;x0, T1 &amp;x1, T2 &amp;x2, T3 &amp;x3, T4 &amp;x4){RD(x0), RD(x1), RD(x2), RD(x3), RD(x4); return x0;}\r\ntemplate&lt;class T0, class T1, class T2, class T3, class T4, class T5&gt; inline T0&amp; RD(T0 &amp;x0, T1 &amp;x1, T2 &amp;x2, T3 &amp;x3, T4 &amp;x4, T5 &amp;x5){RD(x0), RD(x1), RD(x2), RD(x3), RD(x4), RD(x5); return x0;}\r\ntemplate&lt;class T0, class T1, class T2, class T3, class T4, class T5, class T6&gt; inline T0&amp; RD(T0 &amp;x0, T1 &amp;x1, T2 &amp;x2, T3 &amp;x3, T4 &amp;x4, T5 &amp;x5, T6 &amp;x6){RD(x0), RD(x1), RD(x2), RD(x3), RD(x4), RD(x5), RD(x6); return x0;}\r\ntemplate&lt;class T0, class T1&gt; inline void OT(const T0 &amp;x0, const T1 &amp;x1){OT(x0), OT(x1);}\r\ntemplate&lt;class T0, class T1, class T2&gt; inline void OT(const T0 &amp;x0, const T1 &amp;x1, const T2 &amp;x2){OT(x0), OT(x1), OT(x2);}\r\ntemplate&lt;class T0, class T1, class T2, class T3&gt; inline void OT(const T0 &amp;x0, const T1 &amp;x1, const T2 &amp;x2, const T3 &amp;x3){OT(x0), OT(x1), OT(x2), OT(x3);}\r\ntemplate&lt;class T0, class T1, class T2, class T3, class T4&gt; inline void OT(const T0 &amp;x0, const T1 &amp;x1, const T2 &amp;x2, const T3 &amp;x3, const T4 &amp;x4){OT(x0), OT(x1), OT(x2), OT(x3), OT(x4);}\r\ntemplate&lt;class T0, class T1, class T2, class T3, class T4, class T5&gt; inline void OT(const T0 &amp;x0, const T1 &amp;x1, const T2 &amp;x2, const T3 &amp;x3, const T4 &amp;x4, const T5 &amp;x5){OT(x0), OT(x1), OT(x2), OT(x3), OT(x4), OT(x5);}\r\ntemplate&lt;class T0, class T1, class T2, class T3, class T4, class T5, class T6&gt; inline void OT(const T0 &amp;x0, const T1 &amp;x1, const T2 &amp;x2, const T3 &amp;x3, const T4 &amp;x4, const T5 &amp;x5, const T6 &amp;x6){OT(x0), OT(x1), OT(x2), OT(x3), OT(x4), OT(x5), OT(x6);}\r\ninline char&amp; RC(char &amp;a, char &amp;b){RC(a), RC(b); return a;}\r\ninline char&amp; RC(char &amp;a, char &amp;b, char &amp;c){RC(a), RC(b), RC(c); return a;}\r\ninline char&amp; RC(char &amp;a, char &amp;b, char &amp;c, char &amp;d){RC(a), RC(b), RC(c), RC(d); return a;}\r\ninline char&amp; RC(char &amp;a, char &amp;b, char &amp;c, char &amp;d, char &amp;e){RC(a), RC(b), RC(c), RC(d), RC(e); return a;}\r\ninline char&amp; RC(char &amp;a, char &amp;b, char &amp;c, char &amp;d, char &amp;e, char &amp;f){RC(a), RC(b), RC(c), RC(d), RC(e), RC(f); return a;}\r\ninline char&amp; RC(char &amp;a, char &amp;b, char &amp;c, char &amp;d, char &amp;e, char &amp;f, char &amp;g){RC(a), RC(b), RC(c), RC(d), RC(e), RC(f), RC(g); return a;}\r\ninline DB&amp; RF(DB &amp;a, DB &amp;b){RF(a), RF(b); return a;}\r\ninline DB&amp; RF(DB &amp;a, DB &amp;b, DB &amp;c){RF(a), RF(b), RF(c); return a;}\r\ninline DB&amp; RF(DB &amp;a, DB &amp;b, DB &amp;c, DB &amp;d){RF(a), RF(b), RF(c), RF(d); return a;}\r\ninline DB&amp; RF(DB &amp;a, DB &amp;b, DB &amp;c, DB &amp;d, DB &amp;e){RF(a), RF(b), RF(c), RF(d), RF(e); return a;}\r\ninline DB&amp; RF(DB &amp;a, DB &amp;b, DB &amp;c, DB &amp;d, DB &amp;e, DB &amp;f){RF(a), RF(b), RF(c), RF(d), RF(e), RF(f); return a;}\r\ninline DB&amp; RF(DB &amp;a, DB &amp;b, DB &amp;c, DB &amp;d, DB &amp;e, DB &amp;f, DB &amp;g){RF(a), RF(b), RF(c), RF(d), RF(e), RF(f), RF(g); return a;}\r\ninline void RS(char *s1, char *s2){RS(s1), RS(s2);}\r\ninline void RS(char *s1, char *s2, char *s3){RS(s1), RS(s2), RS(s3);}\r\ntemplate&lt;class T0,class T1&gt;inline T0&amp; RDD(T0&amp;a, T1&amp;b){RDD(a),RDD(b); return a;}\r\ntemplate&lt;class T0,class T1,class T2&gt;inline T1&amp; RDD(T0&amp;a, T1&amp;b, T2&amp;c){RDD(a),RDD(b),RDD(c); return a;}\r\n\r\ntemplate&lt;class T&gt; inline void RST(T &amp;A){memset(A, 0, sizeof(A));}\r\ntemplate&lt;class T&gt; inline void FLC(T &amp;A, int x){memset(A, x, sizeof(A));}\r\ntemplate&lt;class T&gt; inline void CLR(T &amp;A){A.clear();}\r\n\r\ntemplate&lt;class T0, class T1&gt; inline void RST(T0 &amp;A0, T1 &amp;A1){RST(A0), RST(A1);}\r\ntemplate&lt;class T0, class T1, class T2&gt; inline void RST(T0 &amp;A0, T1 &amp;A1, T2 &amp;A2){RST(A0), RST(A1), RST(A2);}\r\ntemplate&lt;class T0, class T1, class T2, class T3&gt; inline void RST(T0 &amp;A0, T1 &amp;A1, T2 &amp;A2, T3 &amp;A3){RST(A0), RST(A1), RST(A2), RST(A3);}\r\ntemplate&lt;class T0, class T1, class T2, class T3, class T4&gt; inline void RST(T0 &amp;A0, T1 &amp;A1, T2 &amp;A2, T3 &amp;A3, T4 &amp;A4){RST(A0), RST(A1), RST(A2), RST(A3), RST(A4);}\r\ntemplate&lt;class T0, class T1, class T2, class T3, class T4, class T5&gt; inline void RST(T0 &amp;A0, T1 &amp;A1, T2 &amp;A2, T3 &amp;A3, T4 &amp;A4, T5 &amp;A5){RST(A0), RST(A1), RST(A2), RST(A3), RST(A4), RST(A5);}\r\ntemplate&lt;class T0, class T1, class T2, class T3, class T4, class T5, class T6&gt; inline void RST(T0 &amp;A0, T1 &amp;A1, T2 &amp;A2, T3 &amp;A3, T4 &amp;A4, T5 &amp;A5, T6 &amp;A6){RST(A0), RST(A1), RST(A2), RST(A3), RST(A4), RST(A5), RST(A6);}\r\ntemplate&lt;class T0, class T1&gt; inline void FLC(T0 &amp;A0, T1 &amp;A1, int x){FLC(A0, x), FLC(A1, x);}\r\ntemplate&lt;class T0, class T1, class T2&gt; inline void FLC(T0 &amp;A0, T1 &amp;A1, T2 &amp;A2, int x){FLC(A0, x), FLC(A1, x), FLC(A2, x);}\r\ntemplate&lt;class T0, class T1, class T2, class T3&gt; inline void FLC(T0 &amp;A0, T1 &amp;A1, T2 &amp;A2, T3 &amp;A3, int x){FLC(A0, x), FLC(A1, x), FLC(A2, x), FLC(A3, x);}\r\ntemplate&lt;class T0, class T1, class T2, class T3, class T4&gt; inline void FLC(T0 &amp;A0, T1 &amp;A1, T2 &amp;A2, T3 &amp;A3, T4 &amp;A4, int x){FLC(A0, x), FLC(A1, x), FLC(A2, x), FLC(A3, x), FLC(A4, x);}\r\ntemplate&lt;class T0, class T1, class T2, class T3, class T4, class T5&gt; inline void FLC(T0 &amp;A0, T1 &amp;A1, T2 &amp;A2, T3 &amp;A3, T4 &amp;A4, T5 &amp;A5, int x){FLC(A0, x), FLC(A1, x), FLC(A2, x), FLC(A3, x), FLC(A4, x), FLC(A5, x);}\r\ntemplate&lt;class T0, class T1, class T2, class T3, class T4, class T5, class T6&gt; inline void FLC(T0 &amp;A0, T1 &amp;A1, T2 &amp;A2, T3 &amp;A3, T4 &amp;A4, T5 &amp;A5, T6 &amp;A6, int x){FLC(A0, x), FLC(A1, x), FLC(A2, x), FLC(A3, x), FLC(A4, x), FLC(A5, x), FLC(A6, x);}\r\ntemplate&lt;class T&gt; inline void CLR(priority_queue&lt;T&gt; &amp;Q){while (!Q.empty()) Q.pop();}\r\ntemplate&lt;class T&gt; inline void CLR(stack&lt;T&gt; &amp;S){while (!S.empty()) S.pop();}\r\ntemplate&lt;class T&gt; inline void CLR(queue&lt;T&gt; &amp;Q){while (!Q.empty()) Q.pop();}\r\n\r\ntemplate&lt;class T0, class T1&gt; inline void CLR(T0 &amp;A0, T1 &amp;A1){CLR(A0), CLR(A1);}\r\ntemplate&lt;class T0, class T1, class T2&gt; inline void CLR(T0 &amp;A0, T1 &amp;A1, T2 &amp;A2){CLR(A0), CLR(A1), CLR(A2);}\r\ntemplate&lt;class T0, class T1, class T2, class T3&gt; inline void CLR(T0 &amp;A0, T1 &amp;A1, T2 &amp;A2, T3 &amp;A3){CLR(A0), CLR(A1), CLR(A2), CLR(A3);}\r\ntemplate&lt;class T0, class T1, class T2, class T3, class T4&gt; inline void CLR(T0 &amp;A0, T1 &amp;A1, T2 &amp;A2, T3 &amp;A3, T4 &amp;A4){CLR(A0), CLR(A1), CLR(A2), CLR(A3), CLR(A4);}\r\ntemplate&lt;class T0, class T1, class T2, class T3, class T4, class T5&gt; inline void CLR(T0 &amp;A0, T1 &amp;A1, T2 &amp;A2, T3 &amp;A3, T4 &amp;A4, T5 &amp;A5){CLR(A0), CLR(A1), CLR(A2), CLR(A3), CLR(A4), CLR(A5);}\r\ntemplate&lt;class T0, class T1, class T2, class T3, class T4, class T5, class T6&gt; inline void CLR(T0 &amp;A0, T1 &amp;A1, T2 &amp;A2, T3 &amp;A3, T4 &amp;A4, T5 &amp;A5, T6 &amp;A6){CLR(A0), CLR(A1), CLR(A2), CLR(A3), CLR(A4), CLR(A5), CLR(A6);}\r\ntemplate&lt;class T&gt; inline void CLR(T &amp;A, int n){REP(i, n) CLR(A&#x5B;i]);}\r\n\r\ntemplate&lt;class T&gt; inline bool EPT(T &amp;a){return a.empty();}\r\ntemplate&lt;class T&gt; inline T&amp; SRT(T &amp;A){sort(ALL(A)); return A;}\r\ntemplate&lt;class T, class C&gt; inline T&amp; SRT(T &amp;A, C cmp){sort(ALL(A), cmp); return A;}\r\ntemplate&lt;class T&gt; inline T&amp; RVS(T &amp;A){reverse(ALL(A)); return A;}\r\ntemplate&lt;class T&gt; inline T&amp; UNQQ(T &amp;A){A.resize(unique(ALL(A))-A.begin());return A;}\r\ntemplate&lt;class T&gt; inline T&amp; UNQ(T &amp;A){SRT(A);return UNQQ(A);}\r\ntemplate&lt;class T, class C&gt; inline T&amp; UNQ(T &amp;A, C cmp){SRT(A, cmp);return UNQQ(A);}\r\n\r\n\r\n\/\/}\r\n\r\n\/** Constant List .. **\/ \/\/{\r\n\r\nconst int MOD = int(1e9) + 7;\r\nconst int INF = 0x3f3f3f3f;\r\nconst LL INFF = 0x3f3f3f3f3f3f3f3fLL;\r\nconst DB EPS = 1e-9;\r\nconst DB OO = 1e20;\r\nconst DB PI = acos(-1.0); \/\/M_PI;\r\n\r\nconst int dx&#x5B;] = {-1, 1, 0, 0};\r\nconst int dy&#x5B;] = {0, 0, 1, -1};\r\n\r\n\/\/}\r\n\r\n\/** Add On .. **\/ \/\/{\r\n\/\/ &lt;&lt;= '0. Nichi Joo ., \/\/{\r\n\r\ntemplate&lt;class T&gt; inline bool checkMin(T &amp;a,const T b){return b &lt; a ? a = b, 1 : 0;}\r\ntemplate&lt;class T&gt; inline bool checkMax(T &amp;a,const T b){return a &lt; b ? a = b, 1 : 0;}\r\ntemplate &lt;class T, class C&gt; inline bool checkUpd(T&amp; a, const T b, C c){return c(b,a) ? a = b, 1 : 0;}\r\ntemplate&lt;class T&gt; inline T min(T a, T b, T c){return min(min(a, b), c);}\r\ntemplate&lt;class T&gt; inline T max(T a, T b, T c){return max(max(a, b), c);}\r\ntemplate&lt;class T&gt; inline T min(T a, T b, T c, T d){return min(min(a, b), min(c, d));}\r\ntemplate&lt;class T&gt; inline T max(T a, T b, T c, T d){return max(max(a, b), max(c, d));}\r\ntemplate&lt;class T&gt; inline T min(T a, T b, T c, T d, T e){return min(min(min(a,b),min(c,d)),e);}\r\ntemplate&lt;class T&gt; inline T max(T a, T b, T c, T d, T e){return max(max(max(a,b),max(c,d)),e);}\r\ntemplate&lt;class T&gt; inline T sqr(T a){return a*a;}\r\ntemplate&lt;class T&gt; inline T cub(T a){return a*a*a;}\r\ntemplate&lt;class T&gt; inline T ceil(T x, T y){return (x - 1) \/ y + 1;}\r\ntemplate&lt;class T&gt; T abs(T x){return x&gt;0?x:-x;}\r\ninline int sgn(DB x){return x &lt; -EPS ? -1 : x &gt; EPS;}\r\ninline int sgn(DB x, DB y){return sgn(x - y);}\r\n\r\ninline DB cos(DB a, DB b, DB c){return (sqr(a)+sqr(b)-sqr(c))\/(2*a*b);}\r\ninline DB cot(DB x){return 1.\/tan(x);};\r\ninline DB sec(DB x){return 1.\/cos(x);};\r\ninline DB csc(DB x){return 1.\/sin(x);};\r\n\r\n\/\/}\r\n\/\/ &lt;&lt;= '1. Bitwise Operation ., \/\/{\r\nnamespace BO{\r\n\r\ninline bool _1(int x, int i){return bool(x&amp;1&lt;&lt;i);}\r\ninline bool _1(LL x, int i){return bool(x&amp;1LL&lt;&lt;i);}\r\ninline LL _1(int i){return 1LL&lt;&lt;i;}\r\ninline LL _U(int i){return _1(i) - 1;};\r\n\r\ninline int reverse_bits(int x){\r\n    x = ((x &gt;&gt; 1) &amp; 0x55555555) | ((x &lt;&lt; 1) &amp; 0xaaaaaaaa);\r\n    x = ((x &gt;&gt; 2) &amp; 0x33333333) | ((x &lt;&lt; 2) &amp; 0xcccccccc);\r\n    x = ((x &gt;&gt; 4) &amp; 0x0f0f0f0f) | ((x &lt;&lt; 4) &amp; 0xf0f0f0f0);\r\n    x = ((x &gt;&gt; 8) &amp; 0x00ff00ff) | ((x &lt;&lt; 8) &amp; 0xff00ff00);\r\n    x = ((x &gt;&gt;16) &amp; 0x0000ffff) | ((x &lt;&lt;16) &amp; 0xffff0000);\r\n    return x;\r\n}\r\n\r\ninline LL reverse_bits(LL x){\r\n    x = ((x &gt;&gt; 1) &amp; 0x5555555555555555LL) | ((x &lt;&lt; 1) &amp; 0xaaaaaaaaaaaaaaaaLL);\r\n    x = ((x &gt;&gt; 2) &amp; 0x3333333333333333LL) | ((x &lt;&lt; 2) &amp; 0xccccccccccccccccLL);\r\n    x = ((x &gt;&gt; 4) &amp; 0x0f0f0f0f0f0f0f0fLL) | ((x &lt;&lt; 4) &amp; 0xf0f0f0f0f0f0f0f0LL);\r\n    x = ((x &gt;&gt; 8) &amp; 0x00ff00ff00ff00ffLL) | ((x &lt;&lt; 8) &amp; 0xff00ff00ff00ff00LL);\r\n    x = ((x &gt;&gt;16) &amp; 0x0000ffff0000ffffLL) | ((x &lt;&lt;16) &amp; 0xffff0000ffff0000LL);\r\n    x = ((x &gt;&gt;32) &amp; 0x00000000ffffffffLL) | ((x &lt;&lt;32) &amp; 0xffffffff00000000LL);\r\n    return x;\r\n}\r\n\r\ntemplate&lt;class T&gt; inline bool odd(T x){return x&amp;1;}\r\ntemplate&lt;class T&gt; inline bool even(T x){return !odd(x);}\r\ntemplate&lt;class T&gt; inline T low_bit(T x) {return x &amp; -x;}\r\ntemplate&lt;class T&gt; inline T high_bit(T x) {T p = low_bit(x);while (p != x) x -= p, p = low_bit(x);return p;}\r\ntemplate&lt;class T&gt; inline T cover_bit(T x){T p = 1; while (p &lt; x) p &lt;&lt;= 1;return p;}\r\ntemplate&lt;class T&gt; inline int cover_idx(T x){int p = 0; while (_1(p) &lt; x ) ++p; return p;}\r\n\r\ninline int clz(int x){return __builtin_clz(x);}\r\ninline int clz(LL x){return __builtin_clzll(x);}\r\ninline int ctz(int x){return __builtin_ctz(x);}\r\ninline int ctz(LL x){return __builtin_ctzll(x);}\r\ninline int lg2(int x){return !x ? -1 : 31 - clz(x);}\r\ninline int lg2(LL x){return !x ? -1 : 63 - clz(x);}\r\ninline int low_idx(int x){return !x ? -1 : ctz(x);}\r\ninline int low_idx(LL x){return !x ? -1 : ctz(x);}\r\ninline int high_idx(int x){return lg2(x);}\r\ninline int high_idx(LL x){return lg2(x);}\r\ninline int parity(int x){return __builtin_parity(x);}\r\ninline int parity(LL x){return __builtin_parityll(x);}\r\ninline int count_bits(int x){return __builtin_popcount(x);}\r\ninline int count_bits(LL x){return __builtin_popcountll(x);}\r\n\r\n} using namespace BO;\/\/}\r\n\r\n\r\n\/\/ &lt;&lt;= '2. Number Theory .,\/\/{\r\nnamespace NT{\r\n\/\/#define gcd __gcd\r\ninline LL gcd(LL a, LL b){return b?gcd(b,a%b):a;}\r\ninline LL lcm(LL a, LL b){return a*b\/gcd(a,b);}\r\n\r\ninline void INC(int &amp;a, int b){a += b; if (a &gt;= MOD) a -= MOD;}\r\ninline int sum(int a, int b){a += b; if (a &gt;= MOD) a -= MOD; return a;}\r\n\r\n\/* \u6a21\u6570\u4e24\u500d\u521a\u597d\u8d85 int \u65f6\u3002\r\ninline int sum(uint a, int b){a += b; a %= MOD;if (a &lt; 0) a += MOD; return a;}\r\ninline void INC(int &amp;a, int b){a = sum(a, b);}\r\n*\/\r\n\r\ninline void DEC(int &amp;a, int b){a -= b; if (a &lt; 0) a += MOD;}\r\ninline int dff(int a, int b){a -= b; if (a &lt; 0) a  += MOD; return a;}\r\ninline void MUL(int &amp;a, int b){a = (LL)a * b % MOD;}\r\n\/\/inline int pdt(int a, int b){return (LL)a * b % MOD;}\r\ninline int pdt(int x,int y) {\r\n    int ret; __asm__ __volatile__ (&quot;\\tmull %%ebx\\n\\tdivl %%ecx\\n&quot;:&quot;=d&quot;(ret):&quot;a&quot;(x),&quot;b&quot;(y),&quot;c&quot;(MOD));\r\n    return ret;\r\n}\r\n\r\n\r\ninline int gcd(int m, int n, int &amp;x, int &amp;y){\r\n\r\n    x = 1, y = 0; int xx = 0, yy = 1, q;\r\n\r\n    while (1){\r\n        q = m \/ n, m %= n;\r\n        if (!m){x = xx, y = yy; return n;}\r\n        DEC(x, pdt(q, xx)), DEC(y, pdt(q, yy));\r\n        q = n \/ m, n %= m;\r\n        if (!n) return m;\r\n        DEC(xx, pdt(q, x)), DEC(yy, pdt(q, y));\r\n    }\r\n}\r\n\r\ninline int sum(int a, int b, int c){return sum(a, sum(b, c));}\r\ninline int sum(int a, int b, int c, int d){return sum(sum(a, b), sum(c, d));}\r\ninline int pdt(int a, int b, int c){return pdt(a, pdt(b, c));}\r\ninline int pdt(int a, int b, int c, int d){return pdt(pdt(a, b), pdt(c, d));}\r\n\r\ninline int pow(int a, LL b){\r\n    int c(1); while (b){\r\n        if (b&amp;1) MUL(c, a);\r\n        MUL(a, a), b &gt;&gt;= 1;\r\n    }\r\n    return c;\r\n}\r\n\r\ntemplate&lt;class T&gt; inline T pow(T a, LL b){\r\n    T c(1); while (b){\r\n        if (b&amp;1) c *= a;\r\n        a *= a, b &gt;&gt;= 1;\r\n    }\r\n    return c;\r\n}\r\n\r\ntemplate&lt;class T&gt; inline T pow(T a, int b){\r\n    return pow(a, (LL)b);\r\n}\r\n\r\ninline int _I(int b){\r\n    int a = MOD, x1 = 0, x2 = 1, q; while (1){\r\n        q = a \/ b, a %= b;\r\n        if (!a) return x2;\r\n        DEC(x1, pdt(q, x2));\r\n\r\n        q = b \/ a, b %= a;\r\n        if (!b) return x1;\r\n        DEC(x2, pdt(q, x1));\r\n    }\r\n}\r\n\r\ninline void DIV(int &amp;a, int b){MUL(a, _I(b));}\r\ninline int qtt(int a, int b){return pdt(a, _I(b));}\r\n\r\nstruct Int{\r\n    int val;\r\n\r\n    operator int() const{return val;}\r\n\r\n    Int(int _val = 0):val(_val){\r\n        val %= MOD; if (val &lt; 0) val += MOD;\r\n    }\r\n    Int(LL _val):val(_val){\r\n        _val %= MOD; if (_val &lt; 0) _val += MOD;\r\n        val = _val;\r\n    }\r\n\r\n    Int&amp; operator +=(const int&amp; rhs){INC(val, rhs);rTs;}\r\n    Int operator +(const int&amp; rhs) const{return sum(val, rhs);}\r\n    Int&amp; operator -=(const int&amp; rhs){DEC(val, rhs);rTs;}\r\n    Int operator -(const int&amp; rhs) const{return dff(val, rhs);}\r\n    Int&amp; operator *=(const int&amp; rhs){MUL(val, rhs);rTs;}\r\n    Int operator *(const int&amp; rhs) const{return pdt(val, rhs);}\r\n    Int&amp; operator \/=(const int&amp; rhs){DIV(val, rhs);rTs;}\r\n    Int operator \/(const int&amp; rhs) const{return qtt(val, rhs);}\r\n    Int operator-()const{return MOD-*this;}\r\n};\r\n\r\n} using namespace NT;\/\/}\r\n\r\n\r\n\/\/}\r\n\r\n\r\n\r\n\/** I\/O Accelerator Interface .. **\/ \/\/{\r\n#define g (c=getchar())\r\n#define d isdigit(g)\r\n#define p x=x*10+c-'0'\r\n#define n x=x*10+'0'-c\r\n#define pp l\/=10,p\r\n#define nn l\/=10,n\r\ntemplate&lt;class T&gt; inline T&amp; RD(T &amp;x){\r\n    char c;while(!d);x=c-'0';while(d)p;\r\n    return x;\r\n}\r\ntemplate&lt;class T&gt; inline T&amp; RDD(T &amp;x){\r\n    char c;while(g,c!='-'&amp;&amp;!isdigit(c));\r\n    if (c=='-'){x='0'-g;while(d)n;}\r\n    else{x=c-'0';while(d)p;}\r\n    return x;\r\n}\r\ninline DB&amp; RF(DB &amp;x){\r\n    \/\/scanf(&quot;%lf&quot;, &amp;x);\r\n    char c;while(g,c!='-'&amp;&amp;c!='.'&amp;&amp;!isdigit(c));\r\n    if(c=='-')if(g=='.'){x=0;DB l=1;while(d)nn;x*=l;}\r\n        else{x='0'-c;while(d)n;if(c=='.'){DB l=1;while(d)nn;x*=l;}}\r\n    else if(c=='.'){x=0;DB l=1;while(d)pp;x*=l;}\r\n        else{x=c-'0';while(d)p;if(c=='.'){DB l=1;while(d)pp;x*=l;}}\r\n    return x;\r\n}\r\n#undef nn\r\n#undef pp\r\n#undef n\r\n#undef p\r\n#undef d\r\n#undef g\r\ninline char* RS(char *s){\r\n    \/\/gets(s);\r\n    scanf(&quot;%s&quot;, s);\r\n    return s;\r\n}\r\n\r\nLL last_ans; int Case; template&lt;class T&gt; inline void OT(const T &amp;x){\r\n    \/\/printf(&quot;Case #%d: &quot;, ++Case);\r\n    \/\/printf(&quot;%lld\\n&quot;, x);\r\n    \/\/printf(&quot;%I64d\\n&quot;, x);\r\n    \/\/printf(&quot;%.9f\\n&quot;, x);\r\n    printf(&quot;%d\\n&quot;, x);\r\n    \/\/cout &lt;&lt; x &lt;&lt; endl;\r\n    \/\/last_ans = x;\r\n}\r\n\r\n\r\n\/\/}\/* .................................................................................................................................. *\/\r\n\r\nconst int N = int(1e5) + 9;\r\n\r\n\r\n\r\n#define ri register int\r\n#define rep(io, st, ed) for(ri io = st; io &lt;= ed; io ++)\r\n#define drep(io, ed, st) for(ri io = ed; io &gt;= st; io --)\r\n\r\nnamespace Chairman_Tree {\r\n#define lx c&#x5B;0]&#x5B;x]\r\n#define rx c&#x5B;1]&#x5B;x]\r\n#define ly c&#x5B;0]&#x5B;y]\r\n#define ry c&#x5B;1]&#x5B;y]\r\n#define ml ((l+r)&gt;&gt;1)\r\n#define mr (ml+1)\r\n#define lc lx, lv\r\n#define rc rx, lv\r\n    const int NN = 20*N;\r\n    const int LV = 17;\r\n    int c&#x5B;2]&#x5B;NN], xr&#x5B;NN]; bool cv&#x5B;NN]; int tot;\r\n\r\n    int new_node() {\r\n        ++tot;\r\n        return tot;\r\n    }\r\n\r\n    void put_xor(int x, int lv, int v) {\r\n        if (_1(v, lv)) swap(lx, rx);\r\n        xr&#x5B;x] ^= v;\r\n    }\r\n\r\n    void upd(int x) {\r\n        cv&#x5B;x] = cv&#x5B;lx] &amp;&amp; cv&#x5B;rx];\r\n    }\r\n\r\n    void rls(int x, int lv) {\r\n        if (xr&#x5B;x]) {\r\n            --lv;\r\n            put_xor(rc, xr&#x5B;x]); put_xor(lc, xr&#x5B;x]);\r\n            xr&#x5B;x] = 0;\r\n        }\r\n    }\r\n\r\n    void Init(int &amp;x, int lv, int v) {\r\n        x = new_node();\r\n        if (!~lv) cv&#x5B;x] = 1;\r\n        else {\r\n            if (_1(v, lv--)) Init(rc, v);\r\n            else Init(lc, v);\r\n        }\r\n    }\r\n\r\n    int Merge(int x, int y, int lv = LV) {\r\n        if (!x || !y) return x | y;\r\n        if (!~lv) {\r\n            cv&#x5B;x] |= cv&#x5B;y];\r\n            return x;\r\n        }\r\n        rls(x, lv); rls(y, lv--);\r\n        lx = Merge(lx, ly, lv);\r\n        rx = Merge(rx, ry, lv);\r\n        upd(x);\r\n        return x;\r\n    }\r\n\r\n    int Mex(int x, int lv = LV) {\r\n        if (!x || !~lv) return 0;\r\n        rls(x, lv--);\r\n        return cv&#x5B;lx] ? _1(lv+1) + Mex(rc) : Mex(lc);\r\n    }\r\n\r\n} using namespace Chairman_Tree;\r\n\r\nVI adj&#x5B;N]; int rt&#x5B;N], col&#x5B;N], sg&#x5B;N];\r\nint n;\r\n\r\nvoid dfs(int u = 1, int p = -1) {\r\n    int s = 0;\r\n    for (auto v: adj&#x5B;u]) if (v != p) {\r\n        dfs(v, u); s ^= sg&#x5B;v];\r\n    }\r\n    if (!col&#x5B;u]) Init(rt&#x5B;u], LV, s);\r\n    for (auto v: adj&#x5B;u]) if (v != p) {\r\n        put_xor(rt&#x5B;v], LV, s ^ sg&#x5B;v]);\r\n        rt&#x5B;u] = Merge(rt&#x5B;u], rt&#x5B;v]);\r\n    }\r\n    sg&#x5B;u] = Mex(rt&#x5B;u], LV);\r\n}\r\n\r\nVI Z;\r\n\r\nvoid gao(int u = 1, int p = -1, int SG = 0) {\r\n    for (auto v: adj&#x5B;u]) if (v != p) SG ^= sg&#x5B;v];\r\n    if (!col&#x5B;u] &amp;&amp; !SG) Z.PB(u);\r\n    for (auto v: adj&#x5B;u]) if (v != p) gao(v, u, SG^sg&#x5B;v]);\r\n}\r\n\r\nint main() {\r\n\r\n#ifndef ONLINE_JUDGE\r\n    freopen(&quot;in.txt&quot;, &quot;r&quot;, stdin);\r\n#endif\r\n\r\n    RD(n); REP_1(i, n) RD(col&#x5B;i]); DO(n-1) {\r\n        int x, y; RD(x, y);\r\n        adj&#x5B;x].PB(y); adj&#x5B;y].PB(x);\r\n    }\r\n    dfs();\r\n    if (sg&#x5B;1]) {\r\n        gao(); SRT(Z);\r\n        for (auto z: Z) OT(z);\r\n    } else {\r\n        puts(&quot;-1&quot;);\r\n    }\r\n}\r\n\r\n<\/pre>\n","protected":false},"excerpt":{"rendered":"<p>https:\/\/www.spoj.com\/problems\/COT3\/ https:\/\/blog.csdn.net\/huzecong\/article\/details\/9142121 https:\/\/my.oschina.net\/u\/4321213\/blog\/3694105 \u975e\u5e38 nice \u7684\u9898\u76ee&#8230; \u540c\u65f6\u8003\u5bdf\u7ec4\u5408\u535a\u5f08\u548c\u7ebf\u6bb5\u6811\u5408\u5e76\u3002\u3002\u3002 \u4e0d\u59a8\u5148\u8003\u8651\u7b80\u5355\u7684\u95ee\u9898\uff0c\u5982\u4f55\u8f93\u51fa\u7b2c\u4e00\u6b65\u7684\u65b9\u6848\u3002 \u6211\u4eec\u679a\u4e3e\u7b2c\u4e00\u6b65\u843d\u5728\u54ea\u91cc\uff0c\u90a3\u4e48\u5f62\u6210\u7684\u9ed1\u94fe\u4f1a\u628a\u539f\u6811\u5212\u5206\u4e3a\u82e5\u5e72\u5b50\u6811\uff0c\u6bcf\u7ec4\u5b50\u6811\u76f8\u4e92\u72ec\u7acb\uff0c\u4e8e\u662f\u53d8\u6210\u6e38\u620f\u7684\u548c\uff0c \u6839\u636e SG \u5b9a\u7406\uff0c\u6211\u4eec\u53ea\u8981\u80fd\u6c42\u51fa\u6bcf\u4e2a\u8282\u70b9\u4e3a\u6839\u7684 sg \u503c\u5373\u53ef\u3002 void gao(int u = 1, int p = -1, int SG = 0) { \/\/ \u9012\u5f52\u8fdb\u6765\u7684 SG \u8868\u793a\u5b50\u6811\u5916\u7684\u6e38\u620f for (auto v: adj&#x5B;u]) if (v != p) SG ^= sg&#x5B;v]; \/\/ \u518d xor \u4e0a\u5b50\u6811\u5185\u7684\u6e38\u620f if (!col&#x5B;u] &amp;&amp; !SG) Z.PB(u); for (auto v: [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","enabled":false}}},"categories":[1],"tags":[],"class_list":["post-1758","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_shortlink":"https:\/\/wp.me\/p2tdP7-sm","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/www.shuizilong.com\/house\/wp-json\/wp\/v2\/posts\/1758","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.shuizilong.com\/house\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.shuizilong.com\/house\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.shuizilong.com\/house\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.shuizilong.com\/house\/wp-json\/wp\/v2\/comments?post=1758"}],"version-history":[{"count":1,"href":"https:\/\/www.shuizilong.com\/house\/wp-json\/wp\/v2\/posts\/1758\/revisions"}],"predecessor-version":[{"id":1759,"href":"https:\/\/www.shuizilong.com\/house\/wp-json\/wp\/v2\/posts\/1758\/revisions\/1759"}],"wp:attachment":[{"href":"https:\/\/www.shuizilong.com\/house\/wp-json\/wp\/v2\/media?parent=1758"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.shuizilong.com\/house\/wp-json\/wp\/v2\/categories?post=1758"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.shuizilong.com\/house\/wp-json\/wp\/v2\/tags?post=1758"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}