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

int read() { //快读
    int s = 0, ne = 1; char c = getchar();
    for (; c < '0' || c>'9'; c = getchar()) if (c == '-') ne = -1;
    for (; c >= '0' && c <= '9'; c = getchar()) s = (s << 1) + (s << 3) + c - '0';
    return s * ne;
}

int vis[100005];
int low[100005];
int scc[100005];
int cnt,scc_cnt;
int weight[100005];

vector<vector<int>> graph;
stack<int> s;
void dfs(int x)
{
    int mini = ++cnt;
    vis[x] = mini;
    s.push(x);

    for (int i = 0; i < graph[x].size(); i++)
    {
        int w = graph[x][i];
        if (vis[w] == 0)   //树枝边
        {
            dfs(w);
            mini = min(low[w],mini);
        }
        else if (scc[w] != 0) //若是横叉边 则不需要操作
        {
            mini = min(mini,vis[w]); //前向边与后向边
        }  
    }
    low[x] = mini;
    if (low[x] == vis[x])
    {
        scc_cnt++;
        while (1)
        {
            int cur = s.top(); s.pop();
            scc[cur] = scc_cnt;
            if (cur == x)
                break;
        }
    }
}

int ans=0;
vector<int> memo;
vector<vector<int>> dag;
vector<int> dag_weight;

void dag_dp(int x)
{
    if (memo[x] != -1)
        return;
    
    int tmp = 0;
    for (auto i :dag[x])
    {
        if (memo[i] == -1)
            dag_dp(i);
        tmp = max(tmp, memo[i]);
    }
    memo[x] = tmp + dag_weight[x];
}

int main()
{
    ios::sync_with_stdio(false);
    int n = read();
    int m = read();
    
    memset(weight, 0, sizeof weight);
    for (int i = 1; i <= n; i++)
        weight[i] = read();

    graph.resize(n + 1);
    int u, v;

    for (int i = 1; i <= m; i++)
    {
        u = read(); v = read();
        graph[u].push_back(v);
    }
    cnt = 0;
    scc_cnt = 0;
    memset(low,0,sizeof low);
    memset(vis, 0, sizeof vis);
    memset(scc, 0, sizeof scc);
    
    for(int i=1;i<=n;i++)
    {   
        if(vis[i]==0)
            dfs(i);
    } 
    // dag 建图
    dag.resize(scc_cnt+1);
    dag_weight.resize(scc_cnt+1);
    for (int i = 1; i <= scc_cnt; i++)
        dag_weight[i] = 0;

    for (int i=1;i<=n;i++)
    {
        dag_weight[scc[i]] += weight[i];
        for (int j : graph[i])
        {
            if(scc[j]!=scc[i])
                dag[scc[i]].emplace_back(scc[j]);
        }
    }
    memo.resize(scc_cnt+1);
    for (int i = 1; i <= scc_cnt; i++)
        memo[i] = -1;
    
    for (int i = 1; i <= scc_cnt; i++)
    {
        dag_dp(i);
        ans = max(ans,memo[i]);
    }
    cout << ans;
}

全部超空间。。。 下载数据下来也没问题啊。。