61.187.179.132:8080\/JudgeOnline\/showproblem<\/a>
\u6ce8\u610f\u5230\u8fd9\u6837\u5f62\u6210\u7684\u56fe\u7684\u6bcf\u4e2a\u8054\u901a\u5757\u9876\u4e0a\u5fc5\u7136\u662f\u4e00\u5806\u6811\u6839\u7ec4\u6210\u7684\u73af\uff0c\u90a3\u4e48\u5bf9\u6bcf\u4e2a\u6811\u7528\u6811\u5f62DP\u7b97\u51fa\u9009\u6839\u548c\u4e0d\u9009\u6839\u7684\u6700\u5927\u6536\u5165\uff0c\u7136\u540e\u5c31\u53d8\u6210\u73af\u4e0a\u7684\u95ee\u9898\u4e86\uff0c\u5c31\u6bd4\u8f83\u7b80\u5355\u4e86\u3002\u3002
\u81ea\u5df1\u753b\u7684\u56fe\uff0c\u597d\u60b2\u5267\u56e7\u3002\u3002
![](\"http:\/\/wjmzbmr.com\/wp-content\/uploads\/pic\/c4f63dadd091c0f97dd92a21.jpg\")
<\/p>\n\u4e0d\u8fc7\u611f\u89c9\u6211\u8fd9\u4e2a\u65b9\u6cd5\u8fd8\u4e0d\u9519\uff0c\u5c31\u662f\u4e0d\u662f\u7528\u6811\u5f62DP\u53bb\u7b97\uff0c\u800c\u662f\u4ece\u5e95\u5f80\u4e0a\u66f4\u65b0\uff0c\u6bcf\u4e00\u79cd\u72b6\u6001\u548c\u89c4\u5219\u90fd\u5199\u4e00\u4e2a\u7c7b\u6765\u8868\u793a\u66f4\u4e0d\u5bb9\u6613\u51fa\u9519(*^__^*) \u3002\u3002
Code\uff1a
#include<cstdio>
#include<iostream>
#include<algorithm>
#include<cstring>
#include<queue>
#define rep(i,n) for(int i=0;i<n;i++)
#define pb push_back
using namespace std;
const int inf=~0U>>1,maxn=1000000;
struct StateTree
{
long long A[2];
long long operator()(int v)const{return A[v];}
StateTree(int val=0)
{
A[0]=0;A[1]=val;
}
void Renew(const StateTree&son)
{
A[0]+=max(son(0),son(1));
A[1]+=son(0);
}
}Dp[maxn];
struct StateCircle
{
long long A[2][2];
long long operator()(int l,int r){return A[l][r];}
StateCircle(const StateTree&x)
{
memset(A,0,sizeof(A));
A[0][0]=x(0);
A[1][1]=x(1);
}
void Renew(const StateTree&x)
{
long long Ans[2][2];
rep(i,2)
{
Ans[i][0]=max(A[i][0],A[i][1])+x(0);
Ans[i][1]=A[i][0]+x(1);
}
memcpy(A,Ans,sizeof(A));
}
};
int In[maxn],P[maxn],C[maxn],n;
int main()
{
\/\/freopen("in","r",stdin);
scanf("%d",&n);
rep(i,n) scanf("%d %d",C+i,P+i),In[–P[i]]++,Dp[i]=StateTree(C[i]);
queue<int> Q;
rep(i,n)if(!In[i]) Q.push(i);
while(Q.size())
{
int t=Q.front();Q.pop();
Dp[P[t]].Renew(Dp[t]);
if(–In[P[t]]==0) Q.push(P[t]);
}
long long Ans=0;
rep(i,n)if(In[i]>0)
{
In[i]=0;int t=i;
StateCircle now=StateCircle(Dp[t]);
t=P[t];
while(t!=i)
{
now.Renew(Dp[t]);In[t]=0;
t=P[t];
}
Ans+=max(now(1,0),max(now(0,0),now(0,1)));
}
cout<<Ans<<endl;
} <\/p>\n","protected":false},"excerpt":{"rendered":"
[ZJOI2008]\u9a91\u58eb Time Limit:10000MS Memory Limit:165536KTotal Submit:62 Accepted:30 Case Time Limit:2000MS Description Z\u56fd\u7684\u9a91\u58eb\u56e2\u662f\u4e00\u4e2a\u5f88\u6709\u52bf\u529b\u7684\u7ec4\u7ec7\uff0c\u5e2e\u4f1a\u4e2d\u6c47\u805a\u4e86\u6765\u81ea\u5404\u5730\u7684\u7cbe\u82f1\u3002\u4ed6\u4eec\u52ab\u5bcc\u6d4e\u8d2b\uff0c\u60e9\u6076\u626c\u5584\uff0c\u53d7\u5230\u793e\u4f1a\u5404\u754c\u7684\u8d5e\u626c\u3002 \u6700\u8fd1\u53d1\u751f\u4e86\u4e00\u4ef6\u53ef\u6015\u7684\u4e8b\u60c5\uff0c\u90aa\u6076\u7684Y\u56fd\u53d1\u52a8\u4e86\u4e00\u573a\u9488\u5bf9Z\u56fd\u7684\u4fb5\u7565\u6218\u4e89\u3002\u6218\u706b\u7ef5\u5ef6\u4e94\u767e\u91cc\uff0c\u5728\u548c\u5e73\u73af\u5883\u4e2d\u5b89\u9038\u4e86\u6570\u767e\u5e74\u7684Z\u56fd\u53c8\u600e\u80fd\u62b5\u6321\u7684\u4f4fY\u56fd\u7684\u519b \u961f\u3002\u4e8e\u662f\u4eba\u4eec\u628a\u6240\u6709\u7684\u5e0c\u671b\u90fd\u5bc4\u6258\u5728\u4e86\u9a91\u58eb\u56e2\u7684\u8eab\u4e0a\uff0c\u5c31\u50cf\u671f\u5f85\u6709\u4e00\u4e2a\u771f\u9f99\u5929\u5b50\u7684\u964d\u751f\uff0c\u5e26\u9886\u6b63\u4e49\u6253\u8d25\u90aa\u6076\u3002 \u9a91\u58eb\u56e2\u662f\u80af\u5b9a\u5177\u6709\u6253\u8d25\u90aa\u6076\u52bf\u529b\u7684\u80fd\u529b\u7684\uff0c\u4f46\u662f\u9a91\u58eb\u4eec\u4e92\u76f8\u4e4b\u95f4\u5f80\u5f80\u6709\u4e00\u4e9b\u77db\u76fe\u3002\u6bcf\u4e2a\u9a91\u58eb\u90fd\u6709\u4e14\u4ec5\u6709\u4e00\u4e2a\u81ea\u5df1\u6700\u538c\u6076\u7684\u9a91\u58eb\uff08\u5f53\u7136\u4e0d\u662f\u4ed6\u81ea\u5df1\uff09\uff0c\u4ed6\u662f\u7edd \u5bf9\u4e0d\u4f1a\u4e0e\u81ea\u5df1\u6700\u538c\u6076\u7684\u4eba\u4e00\u540c\u51fa\u5f81\u7684\u3002 \u6218\u706b\u7ef5\u5ef6\uff0c\u4eba\u6c11\u751f\u7075\u6d82\u70ad\uff0c\u7ec4\u7ec7\u8d77\u4e00\u4e2a\u9a91\u58eb\u519b\u56e2\u52a0\u5165\u6218\u6597\u523b\u4e0d\u5bb9\u7f13\uff01\u56fd\u738b\u4ea4\u7ed9\u4e86\u4f60\u4e00\u4e2a\u8270\u5de8\u7684\u4efb\u52a1\uff0c\u4ece\u6240\u6709\u7684\u9a91\u58eb\u4e2d\u9009\u51fa\u4e00\u4e2a\u9a91\u58eb\u519b\u56e2\uff0c\u4f7f\u5f97\u519b\u56e2\u5185\u6ca1\u6709\u77db \u76fe\u7684\u4e24\u4eba\uff08\u4e0d\u5b58\u5728\u4e00\u4e2a\u9a91\u58eb\u4e0e\u4ed6\u6700\u75db\u6068\u7684\u4eba\u4e00\u540c\u88ab\u9009\u5165\u9a91\u58eb\u519b\u56e2\u7684\u60c5\u51b5\uff09\uff0c\u5e76\u4e14\uff0c\u4f7f\u5f97\u8fd9\u652f\u9a91\u58eb\u519b\u56e2\u6700\u5177\u6709\u6218\u6597\u529b\u3002 \u4e3a\u4e86\u63cf\u8ff0\u6218\u6597\u529b\uff0c\u6211\u4eec\u5c06\u9a91\u58eb\u6309\u71671\u81f3N\u7f16\u53f7\uff0c\u7ed9\u6bcf\u540d\u9a91\u58eb\u4e00\u4e2a\u6218\u6597\u529b\u7684\u4f30\u8ba1\uff0c\u4e00\u4e2a\u519b\u56e2\u7684\u6218\u6597\u529b\u4e3a\u6240\u6709\u9a91\u58eb\u7684\u6218\u6597\u529b\u603b\u548c\u3002 Input \u7b2c\u4e00\u884c\u5305\u542b\u4e00\u4e2a\u6b63\u6574\u6570N\uff0c\u63cf\u8ff0\u9a91\u58eb\u56e2\u7684\u4eba\u6570\u3002 \u63a5\u4e0b\u6765N\u884c\uff0c\u6bcf\u884c\u4e24\u4e2a\u6b63\u6574\u6570\uff0c\u6309\u987a\u5e8f\u63cf\u8ff0\u6bcf\u4e00\u540d\u9a91\u58eb\u7684\u6218\u6597\u529b\u548c\u4ed6\u6700\u75db\u6068\u7684\u9a91\u58eb\u3002 Output \u5e94\u5305\u542b\u4e00\u884c\uff0c\u5305\u542b\u4e00\u4e2a\u6574\u6570\uff0c\u8868\u793a\u4f60\u6240\u9009\u51fa\u7684\u9a91\u58eb\u519b\u56e2\u7684\u6218\u6597\u529b\u3002 Sample Input 310 220 330 1 Sample Output 30\u3010\u6570\u636e\u89c4\u6a21\u3011\u5bf9\u4e8e30%\u7684\u6d4b\u8bd5\u6570\u636e\uff0c\u6ee1\u8db3N \u2264 10\uff1b\u5bf9\u4e8e60%\u7684\u6d4b\u8bd5\u6570\u636e\uff0c\u6ee1\u8db3N \u2264 100\uff1b\u5bf9\u4e8e80%\u7684\u6d4b\u8bd5\u6570\u636e\uff0c\u6ee1\u8db3N \u2264 10 000\u3002\u5bf9\u4e8e100%\u7684\u6d4b\u8bd5\u6570\u636e\uff0c\u6ee1\u8db3N \u2264 1 000 000\uff0c\u6bcf\u540d\u9a91\u58eb\u7684\u6218\u6597\u529b\u90fd\u662f\u4e0d\u5927\u4e8e 1 000 000\u7684\u6b63\u6574\u6570\u3002 Source \u554a\u554a\u554a\u3002\u603b\u7b97A\u6389\u4e86\u3002\u300261.187.179.132:8080\/JudgeOnline\/showproblem\u6ce8\u610f\u5230\u8fd9\u6837\u5f62\u6210\u7684\u56fe\u7684\u6bcf\u4e2a\u8054\u901a\u5757\u9876\u4e0a\u5fc5\u7136\u662f\u4e00\u5806\u6811\u6839\u7ec4\u6210\u7684\u73af\uff0c\u90a3\u4e48\u5bf9\u6bcf\u4e2a\u6811\u7528\u6811\u5f62DP\u7b97\u51fa\u9009\u6839\u548c\u4e0d\u9009\u6839\u7684\u6700\u5927\u6536\u5165\uff0c\u7136\u540e\u5c31\u53d8\u6210\u73af\u4e0a\u7684\u95ee\u9898\u4e86\uff0c\u5c31\u6bd4\u8f83\u7b80\u5355\u4e86\u3002\u3002\u81ea\u5df1\u753b\u7684\u56fe\uff0c\u597d\u60b2\u5267\u56e7\u3002\u3002 \u4e0d\u8fc7\u611f\u89c9\u6211\u8fd9\u4e2a\u65b9\u6cd5\u8fd8\u4e0d\u9519\uff0c\u5c31\u662f\u4e0d\u662f\u7528\u6811\u5f62DP\u53bb\u7b97\uff0c\u800c\u662f\u4ece\u5e95\u5f80\u4e0a\u66f4\u65b0\uff0c\u6bcf\u4e00\u79cd\u72b6\u6001\u548c\u89c4\u5219\u90fd\u5199\u4e00\u4e2a\u7c7b\u6765\u8868\u793a\u66f4\u4e0d\u5bb9\u6613\u51fa\u9519(*^__^*) \u3002\u3002Code\uff1a#include<cstdio>#include<iostream>#include<algorithm>#include<cstring>#include<queue>#define rep(i,n) for(int i=0;i<n;i++)#define pb […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[10],"tags":[],"jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/www.shuizilong.com\/wjmzbmr\/index.php?rest_route=\/wp\/v2\/posts\/153"}],"collection":[{"href":"https:\/\/www.shuizilong.com\/wjmzbmr\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.shuizilong.com\/wjmzbmr\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.shuizilong.com\/wjmzbmr\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.shuizilong.com\/wjmzbmr\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=153"}],"version-history":[{"count":0,"href":"https:\/\/www.shuizilong.com\/wjmzbmr\/index.php?rest_route=\/wp\/v2\/posts\/153\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.shuizilong.com\/wjmzbmr\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=153"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.shuizilong.com\/wjmzbmr\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=153"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.shuizilong.com\/wjmzbmr\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=153"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}