传送门
顾名思义，模板awa

#include <cstdio>
#include <cstring>
#include <cmath>
#include <algorithm>
#include <iostream>
#include <string>
#include <queue>
#include <vector>
#define ll long long
using namespace std;
const int M = 300500;
const int N = 30050;
int n, m;
int tot = 0, a, b, tim = 0, top = 0;
int sum[N], col[N], dfs[N], low[N], zhan[N], v[N];
struct node {int to, nxt;
} p[M];
int cnt = -1, fi[N];
void addline(int x, int y) {p[++cnt] = (node){ y, fi[x] };fi[x] = cnt;
}
void tarjan(int x) {dfs[x] = low[x] = ++tim;zhan[++top] = x;for (int i = fi[x]; ~i; i = p[i].nxt) {int v = p[i].to;if (dfs[v] == 0) {tarjan(v);low[x] = min(low[x], low[v]);} else if (col[v] == 0)low[x] = min(low[x], low[v]);}if (low[x] == dfs[x]) {col[x] = ++tot;sum[tot] = v[x];while (zhan[top] != x) {col[zhan[top]] = tot;sum[tot] += v[zhan[top--]];}top--;}return;
}
int dp[N], ru[N];
void topu() {queue<int> q;for (int i = n + 1; i <= tot; i++) {if (ru[i] == 0)q.push(i);}while (!q.empty()) {int now = q.front();q.pop();dp[now] = max(dp[now], sum[now]);for (int i = fi[now]; ~i; i = p[i].nxt) {int v = p[i].to;dp[v] = max(dp[v], dp[now] + sum[v]);ru[v]--;if (ru[v] == 0)q.push(v);}}
}
int main() {scanf("%d%d", &n, &m);tot = n;  //以后的缩点编号从m+1开始for (int i = 1; i <= 3 * n; i++) fi[i] = -1;for (int i = 1; i <= n; i++) {scanf("%d", &v[i]);}for (int i = 1; i <= m; i++) {scanf("%d%d", &a, &b);addline(a, b);}for (int i = 1; i <= n; i++) {if (dfs[i] == 0)tarjan(i);}for (int i = 1; i <= n; i++) {for (int j = fi[i]; ~j; j = p[j].nxt) {int u = p[j].to;if (col[i] != col[u]) {addline(col[i], col[u]);ru[col[u]]++;}}}topu();int ans = 0;for (int i = n + 1; i <= tot; i++) {ans = max(ans, dp[i]);}printf("%d\n", ans);return 0;
}
/*
1
3 3 3 3 3 3 3 3 3 3
*/