MT2040 银行账户

 
#include <bits/stdc++.h>
using namespace std;
const int N = 1005;
int n, m;
struct account
{
    double balance = 0; // 余额
    double alert = 0;   // 警戒值
} a[N];
int main()
{
    cin >> n >> m;
    for (int i = 1; i <= n; i++)
    {
        cin >> a[i].balance;
    }
    double ans = 0;
    while (m--)
    {
        int x, y;
        double z;
        cin >> x >> y >> z;
        if (a[x].balance < z)
            break;
        int p = z;
        double sub = z - p;
 
        a[x].balance -= z;
        a[y].alert += sub;
        a[y].balance += p;
        ans += sub;
        if (a[y].alert > 1)
            break;
    }
    printf("%.2f", ans);
    return 0;
}