@[mmr123](/user/460020)
```cpp
#include <bits/stdc++.h>//by [mmr123](/user/460020)
using namespace std;
int n, m, ti;
bool in[10005];
int dfn[10005];
int low[10005];
int dist[10005];
vector<int> mp[10005];
stack<int> st;
int scc;
int cnt[10005];
int scc_id[10005];
int scc_dist[10005];
vector<int> scc_mp[10005];
queue<int> q;
int mx[10005];
int ans;
void tarjan(int u) {
st.push(u);
in[u] = true;
dfn[u] = low[u] = ++ti;
for (auto v : mp[u]) {
if (!dfn[v]) {
tarjan(v);
low[u] = min(low[u], low[v]);
} else if (in[v]) {
low[u] = min(low[u], dfn[v]);
}
}
if (dfn[u] == low[u]) {
++scc;
while (true) {
int t = st.top();
st.pop();
in[t] = false;
scc_id[t] = scc;
scc_dist[scc] += dist[t];
if (t == u) {
break;
}
}
}
}
int main() {
// freopen("Luogu P3387.in", "r", stdin);
// freopen("Luogu P3387.out", "w", stdout);
cin >> n >> m;
for (int i = 1; i <= n; i++) {
cin >> dist[i];
}
for (int i = 1; i <= m; i++) {
int u, v;
cin >> u >> v;
mp[u].push_back(v);
}
for (int i = 1; i <= n; i++) {
if (!dfn[i]) {
// ti = 0;
tarjan(i);
}
}
for (int i = 1; i <= n; i++) {
for (auto j : mp[i]) {
if (scc_id[i] != scc_id[j]) {
scc_mp[scc_id[i]].push_back(scc_id[j]);
cnt[scc_id[j]]++;
}
}
}
// for (int i = 1; i <= scc; i++) {
// if (cnt[i] == 0) {
// mx[i] = scc_dist[i];
// }
// }
// while (true) {
// int flag = false;
for (int i = 1; i <= scc; i++) {
if (cnt[i] == 0) {
q.push(i);
mx[i] = scc_dist[i];
// cnt[i] = -1;
// flag = true;
}
}
// if (!flag) {
// break;
// }
while (!q.empty()) {
auto now = q.front();
q.pop();
for (auto i : scc_mp[now]) {
cnt[i]--;
mx[i] = max(mx[i], mx[now] + scc_dist[i]);
if (!cnt[i])
{
q.push(i);
}
}
}
// }
for (int i = 1; i <= scc; i++) {
if (mx[i] > ans) {
ans = mx[i];
}
}
cout << ans << endl;
// fclose(stdin);
// fclose(stdout);
// system("pause");
return 0;
}
```
改了点东西，能过，主要是拓扑改了点实现方法。
by Crazyouth @ 2023-11-10 11:33:31
@[Crazyouth](/user/766339) 谢谢大佬
by mmr123 @ 2023-11-10 11:35:37