codevs1506 Messenger (Tarjan) _tarjan

This question many solution, I use Tarjan again to write again

#include <cstdio> #include <iostream> #include <cstring> #include <algorithm> #include <
Stack> using namespace std;
const int MAXN = 2000;
int n,m,to[maxn<<1],head[maxn],cd[maxn],blt[maxn],nxt[maxn<<1],tot,scc[maxn],sz[maxn],tim=0;
BOOL Vis[maxn],flag = 0; struct Edge {int from,to;}
e[maxn<<1];
Stack <int> s;
    void build (int f,int t) {To[++tot] = t;
    Nxt[tot] = head[f];
HEAD[F] = tot; 
int low[maxn],dfn[maxn],scccnt = 0;
    void Dfs (int u) {low[u] = dfn[u] = ++tim;
    S.push (U);
    int V;
        for (int i = head[u]; i = i = Nxt[i]) {v = to[i];
            if (!dfn[v]) {DFS (v);
        Low[u] = min (low[u],low[v]);
        else if (!scc[v]) {Low[u] = min (low[u],dfn[v));
        } if (low[u] = = Dfn[u]) {int x;
        Scccnt + +;
            while (!s.empty ()) {x = S.top ();
            S.pop (); SCC[X] = scccnt;
            sz[scccnt]++;
        if (U = = x) break;
    int main () {scanf ("%d%d", &n,&m);
        for (int i = 1; I <= m + +) {scanf ("%d%d", &e[i].from,& e[i].to);
    Build (E[i].from, e[i].to);
    for (int i = 1; I <= n; i + +) if (!dfn[i]) DFS (i);
    int ans = 0,q = 0;
    int xx[5000];
            for (int i = 1; I <= scccnt i + +) {if (sz[i]>1) {q + +;
        XX[Q] = i;
        for (int j = 1; j <= Q; j + +) for (int i = 1; I <= n; i + +) {if (scc[i] = = Xx[j])
        {Vis[i] = 1;
        for (int i = 1; I <= n; i + +) {if (Vis[i]) puts ("T");
    Else puts ("F");
return 0; }