求大佬帮忙看看qwq

#include <bits/stdc++.h>
using namespace std;

const int N = 1e5 + 10; 
int n, m; 
int w[N], d[N]; 
vector<int> e[N]; 
int dp[N]; 

int main() {
    cin >> n >> m; 
    for (int i = 1; i <= n; ++i) {
        cin >> w[i]; 
    }
    for (int i = 1; i <= m; ++i) {
        int u, v; 
        cin >> u >> v; 
        e[u].push_back(v); 
        d[v]++; 
    }
     // 拓扑排序
    queue<int> q; 
    for (int i = 1; i <= n; ++i) {
        if (!d[i]) {
            q.push(i); 
        }
    }
    vector<int> res; 
    while (!q.empty()) {
        int u = q.front(); 
        q.pop(); 
        res.push_back(u); 
        for (int v : e[u]) {
            d[v]--; 
            if (!d[v]) q.push(v); 
        }
    }

    // 求最长不下降子序列
    int ans = -1;
    for (int i = 0; i < n; ++i) {
        dp[i] = 1;
        for (int j = 0; j < i; ++j) { // 往前找比自己小的数
            if (w[res[i]] >= w[res[j]]) dp[i] = max(dp[j] + 1, dp[i]);
        }
        ans = max(ans, dp[i]);
    }
    cout << ans;
    return 0; 
}
```