某岛

… : "…アッカリ~ン . .. . " .. .
March 18, 2020

2019 ICPC 上海网络赛 Problem A. Lightning Routing I

參考資料

題意

给一颗带边权的树,有两种操作:

  • 𝐶 𝑒𝑖 𝑤𝑖,将第 𝑒𝑖 条边的边权改为 𝑤𝑖。
  • 𝑄 𝑣𝑖,询问距 𝑣𝑖 点最远的点的距离。

解題報告

我來怒貼一發自己的標程。。。

點分樹

/** Micro Mezz Macro Flation -- Overheated Economy ., Last Update: Sep. 22th 2014 **/ //{

/** Header .. **/ //{
#pragma comment(linker, "/STACK:36777216")
//#pragma GCC optimize ("O2")
#define LOCAL
//#include "testlib.h"
#include <functional>
#include <algorithm>
#include <iostream>
#include <fstream>
#include <sstream>
#include <iomanip>
#include <numeric>
#include <cstring>
#include <climits>
#include <cassert>
#include <complex>
#include <cstdio>
#include <string>
#include <vector>
#include <bitset>
#include <queue>
#include <stack>
#include <cmath>
#include <ctime>
#include <list>
#include <set>
#include <map>

//#include <tr1/unordered_set>
//#include <tr1/unordered_map>
//#include <array>

using namespace std;

#define REP(i, n) for (int i=0;i<n;++i)
#define FOR(i, a, b) for (int i=a;i<b;++i)
#define DWN(i, b, a) for (int i=b-1;i>=a;--i)
#define REP_1(i, n) for (int i=1;i<=n;++i)
#define FOR_1(i, a, b) for (int i=a;i<=b;++i)
#define DWN_1(i, b, a) for (int i=b;i>=a;--i)
#define REP_C(i, n) for (int n____=n,i=0;i<n____;++i)
#define FOR_C(i, a, b) for (int b____=b,i=a;i<b____;++i)
#define DWN_C(i, b, a) for (int a____=a,i=b-1;i>=a____;--i)
#define REP_N(i, n) for (i=0;i<n;++i)
#define FOR_N(i, a, b) for (i=a;i<b;++i)
#define DWN_N(i, b, a) for (i=b-1;i>=a;--i)
#define REP_1_C(i, n) for (int n____=n,i=1;i<=n____;++i)
#define FOR_1_C(i, a, b) for (int b____=b,i=a;i<=b____;++i)
#define DWN_1_C(i, b, a) for (int a____=a,i=b;i>=a____;--i)
#define REP_1_N(i, n) for (i=1;i<=n;++i)
#define FOR_1_N(i, a, b) for (i=a;i<=b;++i)
#define DWN_1_N(i, b, a) for (i=b;i>=a;--i)
#define REP_C_N(i, n) for (int n____=(i=0,n);i<n____;++i)
#define FOR_C_N(i, a, b) for (int b____=(i=0,b);i<b____;++i)
#define DWN_C_N(i, b, a) for (int a____=(i=b-1,a);i>=a____;--i)
#define REP_1_C_N(i, n) for (int n____=(i=1,n);i<=n____;++i)
#define FOR_1_C_N(i, a, b) for (int b____=(i=a,b);i<=b____;++i)
#define DWN_1_C_N(i, b, a) for (int a____=(i=b,a);i>=a____;--i)

#define ECH(it, A) for (__typeof(A.begin()) it=A.begin(); it != A.end(); ++it)
#define rECH(it, A) for (__typeof(A.rbegin()) it=A.rbegin(); it != A.rend(); ++it)
#define REP_S(i, str) for (char*i=str;*i;++i)
#define REP_L(i, hd, suc) for (int i=hd;i;i=suc[i])
#define REP_G(i, u) REP_L(i,hd[u],suc)
#define REP_SS(x, s) for (int x=s;x;x=(x-1)&s)
#define DO(n) for ( int ____n = n; ____n-->0; )
#define REP_2(i, j, n, m) REP(i, n) REP(j, m)
#define REP_2_1(i, j, n, m) REP_1(i, n) REP_1(j, m)
#define REP_3(i, j, k, n, m, l) REP(i, n) REP(j, m) REP(k, l)
#define REP_3_1(i, j, k, n, m, l) REP_1(i, n) REP_1(j, m) REP_1(k, l)
#define REP_4(i, j, k, ii, n, m, l, nn) REP(i, n) REP(j, m) REP(k, l) REP(ii, nn)
#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)

#define ALL(A) A.begin(), A.end()
#define LLA(A) A.rbegin(), A.rend()
#define CPY(A, B) memcpy(A, B, sizeof(A))
#define INS(A, P, B) A.insert(A.begin() + P, B)
#define ERS(A, P) A.erase(A.begin() + P)
#define LBD(A, x) (lower_bound(ALL(A), x) - A.begin())
#define UBD(A, x) (upper_bound(ALL(A), x) - A.begin())
#define CTN(T, x) (T.find(x) != T.end())
#define SZ(A) int((A).size())
#define PB push_back
#define MP(A, B) make_pair(A, B)
#define PTT pair<T, T>
#define Ts *this
#define rTs return Ts
#define fi first
#define se second
#define re real()
#define im imag()

#define Rush for(int ____T=RD(); ____T--;)
#define Display(A, n, m) {                      \
REP(i, n){                                    \
REP(j, m-1) cout << A[i][j] << " ";     \
cout << A[i][m-1] << endl;                \
}                                            \
}
#define Display_1(A, n, m) {                    \
REP_1(i, n){                                \
REP_1(j, m-1) cout << A[i][j] << " ";   \
cout << A[i][m] << endl;                \
}                                            \
}

typedef long long LL;
//typedef long double DB;
typedef double DB;
typedef unsigned uint;
typedef unsigned long long uLL;

typedef vector<int> VI;
typedef vector<char> VC;
typedef vector<string> VS;
typedef vector<LL> VL;
typedef vector<DB> VF;
typedef set<int> SI;
typedef set<string> SS;
typedef map<int, int> MII;
typedef map<string, int> MSI;
typedef pair<int, int> PII;
typedef pair<LL, LL> PLL;
typedef vector<PII> VII;
typedef vector<VI> VVI;
typedef vector<VII> VVII;

template<class T> inline T& RD(T &);
template<class T> inline void OT(const T &);
//inline int RD(){int x; return RD(x);}
inline LL RD(){LL x; return RD(x);}
inline DB& RF(DB &);
inline DB RF(){DB x; return RF(x);}
inline char* RS(char *s);
inline char& RC(char &c);
inline char RC();
inline char& RC(char &c){scanf(" %c", &c); return c;}
inline char RC(){char c; return RC(c);}
//inline char& RC(char &c){c = getchar(); return c;}
//inline char RC(){return getchar();}

template<class T> inline T& RDD(T &);
inline LL RDD(){LL x; return RDD(x);}

template<class T0, class T1> inline T0& RD(T0 &x0, T1 &x1){RD(x0), RD(x1); return x0;}
template<class T0, class T1, class T2> inline T0& RD(T0 &x0, T1 &x1, T2 &x2){RD(x0), RD(x1), RD(x2); return x0;}
template<class T0, class T1, class T2, class T3> inline T0& RD(T0 &x0, T1 &x1, T2 &x2, T3 &x3){RD(x0), RD(x1), RD(x2), RD(x3); return x0;}
template<class T0, class T1, class T2, class T3, class T4> inline T0& RD(T0 &x0, T1 &x1, T2 &x2, T3 &x3, T4 &x4){RD(x0), RD(x1), RD(x2), RD(x3), RD(x4); return x0;}
template<class T0, class T1, class T2, class T3, class T4, class T5> inline T0& RD(T0 &x0, T1 &x1, T2 &x2, T3 &x3, T4 &x4, T5 &x5){RD(x0), RD(x1), RD(x2), RD(x3), RD(x4), RD(x5); return x0;}
template<class T0, class T1, class T2, class T3, class T4, class T5, class T6> inline T0& RD(T0 &x0, T1 &x1, T2 &x2, T3 &x3, T4 &x4, T5 &x5, T6 &x6){RD(x0), RD(x1), RD(x2), RD(x3), RD(x4), RD(x5), RD(x6); return x0;}
template<class T0, class T1> inline void OT(const T0 &x0, const T1 &x1){OT(x0), OT(x1);}
template<class T0, class T1, class T2> inline void OT(const T0 &x0, const T1 &x1, const T2 &x2){OT(x0), OT(x1), OT(x2);}
template<class T0, class T1, class T2, class T3> inline void OT(const T0 &x0, const T1 &x1, const T2 &x2, const T3 &x3){OT(x0), OT(x1), OT(x2), OT(x3);}
template<class T0, class T1, class T2, class T3, class T4> inline void OT(const T0 &x0, const T1 &x1, const T2 &x2, const T3 &x3, const T4 &x4){OT(x0), OT(x1), OT(x2), OT(x3), OT(x4);}
template<class T0, class T1, class T2, class T3, class T4, class T5> inline void OT(const T0 &x0, const T1 &x1, const T2 &x2, const T3 &x3, const T4 &x4, const T5 &x5){OT(x0), OT(x1), OT(x2), OT(x3), OT(x4), OT(x5);}
template<class T0, class T1, class T2, class T3, class T4, class T5, class T6> inline void OT(const T0 &x0, const T1 &x1, const T2 &x2, const T3 &x3, const T4 &x4, const T5 &x5, const T6 &x6){OT(x0), OT(x1), OT(x2), OT(x3), OT(x4), OT(x5), OT(x6);}
inline char& RC(char &a, char &b){RC(a), RC(b); return a;}
inline char& RC(char &a, char &b, char &c){RC(a), RC(b), RC(c); return a;}
inline char& RC(char &a, char &b, char &c, char &d){RC(a), RC(b), RC(c), RC(d); return a;}
inline char& RC(char &a, char &b, char &c, char &d, char &e){RC(a), RC(b), RC(c), RC(d), RC(e); return a;}
inline char& RC(char &a, char &b, char &c, char &d, char &e, char &f){RC(a), RC(b), RC(c), RC(d), RC(e), RC(f); return a;}
inline char& RC(char &a, char &b, char &c, char &d, char &e, char &f, char &g){RC(a), RC(b), RC(c), RC(d), RC(e), RC(f), RC(g); return a;}
inline DB& RF(DB &a, DB &b){RF(a), RF(b); return a;}
inline DB& RF(DB &a, DB &b, DB &c){RF(a), RF(b), RF(c); return a;}
inline DB& RF(DB &a, DB &b, DB &c, DB &d){RF(a), RF(b), RF(c), RF(d); return a;}
inline DB& RF(DB &a, DB &b, DB &c, DB &d, DB &e){RF(a), RF(b), RF(c), RF(d), RF(e); return a;}
inline DB& RF(DB &a, DB &b, DB &c, DB &d, DB &e, DB &f){RF(a), RF(b), RF(c), RF(d), RF(e), RF(f); return a;}
inline DB& RF(DB &a, DB &b, DB &c, DB &d, DB &e, DB &f, DB &g){RF(a), RF(b), RF(c), RF(d), RF(e), RF(f), RF(g); return a;}
inline void RS(char *s1, char *s2){RS(s1), RS(s2);}
inline void RS(char *s1, char *s2, char *s3){RS(s1), RS(s2), RS(s3);}
template<class T0,class T1>inline T0& RDD(T0&a, T1&b){RDD(a),RDD(b); return a;}
template<class T0,class T1,class T2>inline T1& RDD(T0&a, T1&b, T2&c){RDD(a),RDD(b),RDD(c); return a;}

template<class T> inline void RST(T &A){memset(A, 0, sizeof(A));}
template<class T> inline void FLC(T &A, int x){memset(A, x, sizeof(A));}
template<class T> inline void CLR(T &A){A.clear();}

template<class T0, class T1> inline void RST(T0 &A0, T1 &A1){RST(A0), RST(A1);}
template<class T0, class T1, class T2> inline void RST(T0 &A0, T1 &A1, T2 &A2){RST(A0), RST(A1), RST(A2);}
template<class T0, class T1, class T2, class T3> inline void RST(T0 &A0, T1 &A1, T2 &A2, T3 &A3){RST(A0), RST(A1), RST(A2), RST(A3);}
template<class T0, class T1, class T2, class T3, class T4> inline void RST(T0 &A0, T1 &A1, T2 &A2, T3 &A3, T4 &A4){RST(A0), RST(A1), RST(A2), RST(A3), RST(A4);}
template<class T0, class T1, class T2, class T3, class T4, class T5> inline void RST(T0 &A0, T1 &A1, T2 &A2, T3 &A3, T4 &A4, T5 &A5){RST(A0), RST(A1), RST(A2), RST(A3), RST(A4), RST(A5);}
template<class T0, class T1, class T2, class T3, class T4, class T5, class T6> inline void RST(T0 &A0, T1 &A1, T2 &A2, T3 &A3, T4 &A4, T5 &A5, T6 &A6){RST(A0), RST(A1), RST(A2), RST(A3), RST(A4), RST(A5), RST(A6);}
template<class T0, class T1> inline void FLC(T0 &A0, T1 &A1, int x){FLC(A0, x), FLC(A1, x);}
template<class T0, class T1, class T2> inline void FLC(T0 &A0, T1 &A1, T2 &A2, int x){FLC(A0, x), FLC(A1, x), FLC(A2, x);}
template<class T0, class T1, class T2, class T3> inline void FLC(T0 &A0, T1 &A1, T2 &A2, T3 &A3, int x){FLC(A0, x), FLC(A1, x), FLC(A2, x), FLC(A3, x);}
template<class T0, class T1, class T2, class T3, class T4> inline void FLC(T0 &A0, T1 &A1, T2 &A2, T3 &A3, T4 &A4, int x){FLC(A0, x), FLC(A1, x), FLC(A2, x), FLC(A3, x), FLC(A4, x);}
template<class T0, class T1, class T2, class T3, class T4, class T5> inline void FLC(T0 &A0, T1 &A1, T2 &A2, T3 &A3, T4 &A4, T5 &A5, int x){FLC(A0, x), FLC(A1, x), FLC(A2, x), FLC(A3, x), FLC(A4, x), FLC(A5, x);}
template<class T0, class T1, class T2, class T3, class T4, class T5, class T6> inline void FLC(T0 &A0, T1 &A1, T2 &A2, T3 &A3, T4 &A4, T5 &A5, T6 &A6, int x){FLC(A0, x), FLC(A1, x), FLC(A2, x), FLC(A3, x), FLC(A4, x), FLC(A5, x), FLC(A6, x);}
template<class T> inline void CLR(priority_queue<T, vector<T>, less<T> > &Q){while (!Q.empty()) Q.pop();}
template<class T> inline void CLR(priority_queue<T, vector<T>, greater<T> > &Q){while (!Q.empty()) Q.pop();}
template<class T> inline void CLR(stack<T> &S){while (!S.empty()) S.pop();}
template<class T> inline void CLR(queue<T> &Q){while (!Q.empty()) Q.pop();}

template<class T0, class T1> inline void CLR(T0 &A0, T1 &A1){CLR(A0), CLR(A1);}
template<class T0, class T1, class T2> inline void CLR(T0 &A0, T1 &A1, T2 &A2){CLR(A0), CLR(A1), CLR(A2);}
template<class T0, class T1, class T2, class T3> inline void CLR(T0 &A0, T1 &A1, T2 &A2, T3 &A3){CLR(A0), CLR(A1), CLR(A2), CLR(A3);}
template<class T0, class T1, class T2, class T3, class T4> inline void CLR(T0 &A0, T1 &A1, T2 &A2, T3 &A3, T4 &A4){CLR(A0), CLR(A1), CLR(A2), CLR(A3), CLR(A4);}
template<class T0, class T1, class T2, class T3, class T4, class T5> inline void CLR(T0 &A0, T1 &A1, T2 &A2, T3 &A3, T4 &A4, T5 &A5){CLR(A0), CLR(A1), CLR(A2), CLR(A3), CLR(A4), CLR(A5);}
template<class T0, class T1, class T2, class T3, class T4, class T5, class T6> inline void CLR(T0 &A0, T1 &A1, T2 &A2, T3 &A3, T4 &A4, T5 &A5, T6 &A6){CLR(A0), CLR(A1), CLR(A2), CLR(A3), CLR(A4), CLR(A5), CLR(A6);}
template<class T> inline void CLR(T &A, int n){REP(i, n) CLR(A[i]);}

template<class T> inline bool EPT(T &a){return a.empty();}
template<class T> inline T& SRT(T &A){sort(ALL(A)); return A;}
template<class T, class C> inline T& SRT(T &A, C B){sort(ALL(A), B); return A;}
template<class T> inline T& RVS(T &A){reverse(ALL(A)); return A;}
template<class T> inline T& UNQQ(T &A){A.resize(unique(ALL(A))-A.begin());return A;}
template<class T> inline T& UNQ(T &A){SRT(A);return UNQQ(A);}


//}

/** Constant List .. **/ //{

const int MOD = int(1e9) + 7;
const int INF = 0x3f3f3f3f;
const LL INFF = 0x3f3f3f3f3f3f3f3fLL;
const DB EPS = 1e-9;
const DB OO = 1e20;
const DB PI = acos(-1.0); //M_PI;

const int dx[] = {-1, 0, 1, 0};
const int dy[] = {0, 1, 0, -1};

//}

/** Add On .. **/ //{
// <<= '0. Nichi Joo ., //{

template<class T> inline T& checkMin(T &a,const T b){if (b<a) a=b;return a;}
template<class T> inline T& checkMax(T &a,const T b){if (a<b) a=b;return a;}
template<class T> inline T& checkMin(T &a, T &b, const T x){checkMin(a, x), checkMin(b, x);return a;}
template<class T> inline T& checkMax(T &a, T &b, const T x){checkMax(a, x), checkMax(b, x);return a;}
template <class T, class C> inline T& checkMin(T& a, const T b, C c){if (c(b,a)) a = b;return a;}
template <class T, class C> inline T& checkMax(T& a, const T b, C c){if (c(a,b)) a = b;return a;}
template<class T> inline T min(T a, T b, T c){return min(min(a, b), c);}
template<class T> inline T max(T a, T b, T c){return max(max(a, b), c);}
template<class T> inline T min(T a, T b, T c, T d){return min(min(a, b), min(c, d));}
template<class T> inline T max(T a, T b, T c, T d){return max(max(a, b), max(c, d));}
template<class T> inline T min(T a, T b, T c, T d, T e){return min(min(min(a,b),min(c,d)),e);}
template<class T> inline T max(T a, T b, T c, T d, T e){return max(max(max(a,b),max(c,d)),e);}
template<class T> inline T sqr(T a){return a*a;}
template<class T> inline T cub(T a){return a*a*a;}
template<class T> inline T ceil(T x, T y){return (x - 1) / y + 1;}
template<class T> T abs(T x){return x>0?x:-x;}
inline int sgn(DB x){return x < -EPS ? -1 : x > EPS;}
inline int sgn(DB x, DB y){return sgn(x - y);}

inline DB cos(DB a, DB b, DB c){return (sqr(a)+sqr(b)-sqr(c))/(2*a*b);}
inline DB cot(DB x){return 1./tan(x);};
inline DB sec(DB x){return 1./cos(x);};
inline DB csc(DB x){return 1./sin(x);};

//}
// <<= '1. Bitwise Operation ., //{
namespace BO{
    
    inline bool _1(int x, int i){return bool(x&1<<i);}
    inline bool _1(LL x, int i){return bool(x&1LL<<i);}
    inline LL _1(int i){return 1LL<<i;}
    inline LL _U(int i){return _1(i) - 1;};
    
    inline int reverse_bits(int x){
        x = ((x >> 1) & 0x55555555) | ((x << 1) & 0xaaaaaaaa);
        x = ((x >> 2) & 0x33333333) | ((x << 2) & 0xcccccccc);
        x = ((x >> 4) & 0x0f0f0f0f) | ((x << 4) & 0xf0f0f0f0);
        x = ((x >> 8) & 0x00ff00ff) | ((x << 8) & 0xff00ff00);
        x = ((x >>16) & 0x0000ffff) | ((x <<16) & 0xffff0000);
        return x;
    }
    
    inline LL reverse_bits(LL x){
        x = ((x >> 1) & 0x5555555555555555LL) | ((x << 1) & 0xaaaaaaaaaaaaaaaaLL);
        x = ((x >> 2) & 0x3333333333333333LL) | ((x << 2) & 0xccccccccccccccccLL);
        x = ((x >> 4) & 0x0f0f0f0f0f0f0f0fLL) | ((x << 4) & 0xf0f0f0f0f0f0f0f0LL);
        x = ((x >> 8) & 0x00ff00ff00ff00ffLL) | ((x << 8) & 0xff00ff00ff00ff00LL);
        x = ((x >>16) & 0x0000ffff0000ffffLL) | ((x <<16) & 0xffff0000ffff0000LL);
        x = ((x >>32) & 0x00000000ffffffffLL) | ((x <<32) & 0xffffffff00000000LL);
        return x;
    }
    
    template<class T> inline bool odd(T x){return x&1;}
    template<class T> inline bool even(T x){return !odd(x);}
    template<class T> inline T low_bit(T x) {return x & -x;}
    template<class T> inline T high_bit(T x) {T p = low_bit(x);while (p != x) x -= p, p = low_bit(x);return p;}
    template<class T> inline T cover_bit(T x){T p = 1; while (p < x) p <<= 1;return p;}
    template<class T> inline int cover_idx(T x){int p = 0; while (_1(p) < x ) ++p; return p;}
    
    inline int clz(int x){return __builtin_clz(x);}
    inline int clz(LL x){return __builtin_clzll(x);}
    inline int ctz(int x){return __builtin_ctz(x);}
    inline int ctz(LL x){return __builtin_ctzll(x);}
    inline int lg2(int x){return !x ? -1 : 31 - clz(x);}
    inline int lg2(LL x){return !x ? -1 : 63 - clz(x);}
    inline int low_idx(int x){return !x ? -1 : ctz(x);}
    inline int low_idx(LL x){return !x ? -1 : ctz(x);}
    inline int high_idx(int x){return lg2(x);}
    inline int high_idx(LL x){return lg2(x);}
    inline int parity(int x){return __builtin_parity(x);}
    inline int parity(LL x){return __builtin_parityll(x);}
    inline int count_bits(int x){return __builtin_popcount(x);}
    inline int count_bits(LL x){return __builtin_popcountll(x);}
    
} using namespace BO;//}


// <<= '2. Number Theory .,//{
namespace NT{
    
    inline void INC(int &a, int b){a += b; if (a >= MOD) a -= MOD;}
    inline int sum(int a, int b){a += b; if (a >= MOD) a -= MOD; return a;}
    /* 模�两��好� int ��
     inline int sum(uint a, int b){a += b; a %= MOD;if (a < 0) a += MOD; return a;}
     inline void INC(int &a, int b){a = sum(a, b);}
     */
    
    inline void DEC(int &a, int b){a -= b; if (a < 0) a += MOD;}
    inline int dff(int a, int b){a -= b; if (a < 0) a  += MOD; return a;}
    inline void MUL(int &a, int b){a = (LL)a * b % MOD;}
    inline int pdt(int a, int b){return (LL)a * b % MOD;}
    
    inline int gcd(int m, int n, int &x, int &y){
        
        x = 1, y = 0; int xx = 0, yy = 1, q;
        
        while (1){
            q = m / n, m %= n;
            if (!m){x = xx, y = yy; return n;}
            DEC(x, pdt(q, xx)), DEC(y, pdt(q, yy));
            q = n / m, n %= m;
            if (!n) return m;
            DEC(xx, pdt(q, x)), DEC(yy, pdt(q, y));
        }
    }
    
    inline int sum(int a, int b, int c){return sum(a, sum(b, c));}
    inline int sum(int a, int b, int c, int d){return sum(sum(a, b), sum(c, d));}
    inline int pdt(int a, int b, int c){return pdt(a, pdt(b, c));}
    inline int pdt(int a, int b, int c, int d){return pdt(pdt(a, b), pdt(c, d));}
    
    inline int pow(int a, LL b){
        int c(1); while (b){
            if (b&1) MUL(c, a);
            MUL(a, a), b >>= 1;
        }
        return c;
    }
    
    template<class T> inline T pow(T a, LL b){
        T c(1); while (b){
            if (b&1) c *= a;
            a *= a, b >>= 1;
        }
        return c;
    }
    
    template<class T> inline T pow(T a, int b){
        return pow(a, (LL)b);
    }
    
    inline int _I(int b){
        int a = MOD, x1 = 0, x2 = 1, q; while (1){
            q = a / b, a %= b;
            if (!a) return x2;
            DEC(x1, pdt(q, x2));
            
            q = b / a, b %= a;
            if (!b) return x1;
            DEC(x2, pdt(q, x1));
        }
    }
    
    inline void DIV(int &a, int b){MUL(a, _I(b));}
    inline int qtt(int a, int b){return pdt(a, _I(b));}
    
    struct Int{
        int val;
        
        operator int() const{return val;}
        
        Int(int val = 0):val(val){
            val %= MOD; if (val < 0) val += MOD;
        }
        Int(LL _val){
            _val %= MOD; if (_val < 0) _val += MOD;
            val = _val;
        }
        Int& operator +=(const int& rhs){INC(val, rhs);rTs;}
        Int operator +(const int& rhs) const{return sum(val, rhs);}
        Int& operator -=(const int& rhs){DEC(val, rhs);rTs;}
        Int operator -(const int& rhs) const{return dff(val, rhs);}
        Int& operator *=(const int& rhs){MUL(val, rhs);rTs;}
        Int operator *(const int& rhs) const{return pdt(val, rhs);}
        Int& operator /=(const int& rhs){DIV(val, rhs);rTs;}
        Int operator /(const int& rhs) const{return qtt(val, rhs);}
        Int operator-()const{return MOD-*this;}
    };
    
} using namespace NT;//}


//}



/** I/O Accelerator Interface .. **/ //{
#define g (c=getchar())
#define d isdigit(g)
#define p x=x*10+c-'0'
#define n x=x*10+'0'-c
#define pp l/=10,p
#define nn l/=10,n
template<class T> inline T& RD(T &x){
    char c;while(!d);x=c-'0';while(d)p;
    return x;
}
template<class T> inline T& RDD(T &x){
    char c;while(g,c!='-'&&!isdigit(c));
    if (c=='-'){x='0'-g;while(d)n;}
    else{x=c-'0';while(d)p;}
    return x;
}
inline DB& RF(DB &x){
    //scanf("%lf", &x);
    char c;while(g,c!='-'&&c!='.'&&!isdigit(c));
    if(c=='-')if(g=='.'){x=0;DB l=1;while(d)nn;x*=l;}
    else{x='0'-c;while(d)n;if(c=='.'){DB l=1;while(d)nn;x*=l;}}
    else if(c=='.'){x=0;DB l=1;while(d)pp;x*=l;}
    else{x=c-'0';while(d)p;if(c=='.'){DB l=1;while(d)pp;x*=l;}}
    return x;
}
#undef nn
#undef pp
#undef n
#undef p
#undef d
#undef g
inline char* RS(char *s){
    //gets(s);
    scanf("%s", s);
    return s;
}

LL last_ans; int Case; template<class T> inline void OT(const T &x){
    //printf("Case #%d: ", ++Case);
    printf("%lld\n", x);
    //printf("%.9f\n", x);
    //printf("%d\n", x);
    //cout << x << endl;
    last_ans = x;
}

//}/* .................................................................................................................................. */

const int N = int(1e5) + 9, M = N+N, LV = 20;

typedef pair<LL, pair<int, int>> diameter;


namespace Original_Tree {
    int hd[N], prd[M], suc[M], to[M]; LL ww[N];
    multiset<diameter> Diameter; int n;
    
    int bg[N], ed[N], t0; // dfs order
    int ST[LV+1][M], st[N], dep[N]; int t1; // euler order
    
} using namespace Original_Tree;

namespace BIT{
    LL C[N];
    LL Sum(int x){
        LL z=0; for (;x;x^=low_bit(x)) z += C[x];
        return z;
    }
    void Add(int x, LL d){
        for(;x<=n;x+=low_bit(x)) C[x] += d;
    }
} //using namespace BIT;

inline bool elder(int a, int b){
    return dep[a] < dep[b];
}

inline int lca(int a, int b){
    int l = st[a], r = st[b]; if (l > r) swap(l, r); ++r; int lv = lg2(r-l);
    return min(ST[lv][l], ST[lv][r-(1<<lv)], elder);
}

LL dist(int a, int b) {
    return BIT::Sum(bg[a]) + BIT::Sum(bg[b]) - BIT::Sum(bg[lca(a, b)]) * 2;
}

#define aa to[i^1]
#define bb to[i]
#define v bb

void dfs(int u = 1, int p = -1) {
    ST[0][st[u] = ++t1] = u;
    bg[u] = ++t0;
    REP_G(i, u) if (v != p) {
        dep[v] = dep[u] + 1;
        dfs(v, u);
        ST[0][++t1] = u;
        LL w = ww[i/2];
        BIT::Add(bg[v], w);
        BIT::Add(ed[v]+1, -w);
    }
    ed[u] = t0;
}




struct SGT {
#define lx (x<<1)
#define rx (lx|1)
#define ml (l+r>>1)
#define mr (ml+1)
#define lc lx, l, ml
#define rc rx, mr, r
#define xx x, l, r
#define rt 1, 1, n
    
    map<int, pair<int, int>> dfn; // edge -> st, ed
    map<int, int> reverse_st;     // st -> edge, used to record two endpoints of the Diameter
    int n, a, b; LL d;
    
    struct node {
        LL d; pair<LL, int> d0;
    };
    
    vector<node> T;
    
    void upd(int x) {
        T[x].d0 = max(T[lx].d0, T[rx].d0);
    }
    
    void inc(int x, LL d) {
        T[x].d0.fi += d;
        T[x].d += d;
    }
    
    void rls(int x) {
        LL &d = T[x].d;
        if (d) {
            inc(lx, d); inc(rx, d);
            d = 0;
        }
    }
    
    void Modify(int x, int l, int r) {
        if (a <= l && r <= b){
            inc(x, d);
        }
        else{
            rls(x);
            if (a < mr) Modify(lc);
            if (ml < b) Modify(rc);
            upd(x);
        }
    }
    
    void Build(int x, int l, int r) {
        // cout << x << " " << l << " " << r << endl;
        if (l == r) {
            T[x].d0 = {0, reverse_st[l]};
        } else {
            Build(lc);
            Build(rc);
            upd(x);
        }
    }
    
    void Modify(int x, LL delta) {
        a = dfn[x].fi, b = dfn[x].se, d = delta;
        //  cout << "C: " << a << " " << b << " " << d << endl;
        Modify(rt);
    }
    
    void Build() {
        if (n == 0) return;
        T.resize(4*n); Build(rt);
        ECH(it, dfn) {
            a = it->se.fi, b = it->se.se, d = ww[it->fi];
            // cout << " " << a << " " << b << " " << d << endl;
            Modify(rt);
        }
    }
    
#undef rt
#undef xx
#undef rc
#undef lc
#undef rx
#undef lx
};

struct StarTree {
    map<int, SGT> T;      // root -> segment tree
    map<int, int> belong; // edge -> root
    multiset<pair<LL, int>> path; // longest path from root in each tree
    int root;
    
    diameter GetDiameter() {
        auto it = path.rbegin();
        diameter d = {it->fi, {it->se, root}}; ++it;
        if (path.size() >= 2) {
            d.fi += it->fi;
            d.se.se = it->se;
        }
        //cout << "___" << root << " " << endl;
        //ECH(it, path) cout << it->fi << " " << it->se << endl;
        //cout << d.fi << " : " << d.se.fi << " " << d.se.se << endl;
        
        return d;
    }
    
    void Build() {
        if (T.empty()) return;
        ECH(it, T) {
            it->se.Build();
            path.insert(it->se.T[1].d0);
        }
        
        Diameter.insert(GetDiameter());
    }
    
    void Modify(int i, LL d) {
        int r = belong[i];
        Diameter.erase(Diameter.find(GetDiameter()));
        path.erase(path.find(T[r].T[1].d0));
        T[r].Modify(i, d);
        path.insert(T[r].T[1].d0);
        Diameter.insert(GetDiameter());
    }
    
} T[N];


namespace TDC{
    
    int sz[N];
    int par[N], leaf[N];
    int nn, c, cc;
    
    inline void del(int i){
        if (i == hd[aa]) prd[hd[aa] = suc[i]] = 0;
        else prd[suc[i]] = prd[i], suc[prd[i]] = suc[i];
    }
    
    void dfsc(int u, int p = 0){
        int ss = 0; sz[u] = 1; REP_G(i, u) if (v != p){
            dfsc(v, u), sz[u] += sz[v];
            checkMax(ss, sz[v]);
        }
        checkMax(ss, nn - sz[u]);
        if (ss <= cc) cc = ss, c = u;
    }
    
    void dfs0(int u = c, int r = -1, int p = -1){
        if (~p) {
            leaf[p/2] = c;
            par[u] = c;
            T.belong[p/2] = r;
            T.T[r].reverse_st[T.T[r].dfn[p/2].fi = ++T.T[r].n] = u;
        }
        sz[u] = 1;
        REP_G(i, u) if (i != p) {
            dfs0(v, ~p ? r : i/2, i^1); sz[u] += sz[v];
        }
        if (~p) T.T[r].dfn[p/2].se = T.T[r].n;
    }
    
    void gao(int u = 1){
        cc = INF, dfsc(u), dfs0();
        T.root = c; T.Build();
        REP_G(i, c) {
            del(i^1), nn = sz[v], gao(v);
        }
    }
    
    
    void Modify(int i, LL w){
        ++i;
        int u = leaf[i]; LL d = w - ww[i];
        T[u].Modify(i, d);
        
        while (par[u]) {
            u = par[u];
            T[u].Modify(i, d);
        }
        ww[i] = w;
    }
    
#undef v
    
} using namespace TDC;


void Query() {
    int x; RD(x); // cout << " " << x << endl;
    int a = Diameter.rbegin()->se.fi, b =  Diameter.rbegin()->se.se;
    //cout << Diameter.rbegin()->fi << endl;
    LL z = max(dist(x, a), dist(x, b));
    //cout << x << " " << a << " " << b << endl;
    //cout << "d24 " << dist(2, 4) << endl;
    OT(z);
}

void Modify() {
    int i; LL w; RD(i); RD(w);

    int u = leaf[i]; LL d = w - ww[i];
    T[u].Modify(i, d);
    
    while (par[u]) {
        u = par[u];
        T[u].Modify(i, d);
    }
    int a = elder(to[i*2], to[i*2+1]) ? to[i*2+1] : to[i*2];
    //cout << a << " " << bg[a] << " " << ed[a] << " " << d <<endl;
    BIT::Add(bg[a], d);
    BIT::Add(ed[a]+1, -d);
    ww[i] = w;
}


int main(){
    
#ifndef ONLINE_JUDGE
    freopen("/users/minakokojima/Documents/github/ACM-Training/Workspace/in.txt", "r", stdin);
    //freopen("/users/minakokojima/ACM-Training/Workspace/out.txt", "w", stdout);
#endif
    
    RD(n);
    
    fill(hd+1, hd+n+1, 0); FOR(i, 2, n<<1){
        RD(aa, bb, ww[i/2]);
        suc[prd[hd[aa]] = i] = hd[aa], hd[aa] = i; ++i;
        suc[prd[hd[aa]] = i] = hd[aa], hd[aa] = i;
    }
    
    dfs();
    for ( int lv = 1 ; (1 << lv) <= t1 ; lv ++ ){
        for ( int i = 1 ; i + (1 << lv)  <= t1 + 1 ; i ++ )
            ST[lv][i] = min(ST[lv-1][i], ST[lv-1][i + (1<<(lv-1))], elder);
    }
    
    nn = n, gao();
    
    //REP_1(i, n) cout << i << " " << par[i] << " " << leaf[i] << endl;
    
    Rush {
        char cmd; RC(cmd); {
            if (cmd == 'Q') {
                Query();
            } else {
                Modify();
            }
        }
        // int t; LL v; RD(t, v);
        // Modify(t, v);
        //OT(Diameter.rbegin()->fi);
    }
}
// 5865