#include "bits/stdc++.h"

typedef long long ll;

using namespace std;
const int N = 2e5 + 10;
int n, m;
ll A[N], val[N];
ll x[N];
int t[N];

void solve() {
    cin >> n >> m;
    for (int i = 1; i <= n; i++) cin >> A[i], val[i] = A[i];
    for (int i = 1; i <= m; i++) cin >> x[i] >> t[i];
    t[m + 1] = 0;

    ll tmp = 0, last = 0;
    for (int i = 1; i <= n; i++) tmp += val[i];
    for (int l = 1; l <= m; l++) {
        if (tmp >= x[l]) {
            last += x[l] - x[l - 1];
            if (last >= A[t[l]]) {
                last -= A[t[l]];
                tmp += A[t[l]];
            } else {
                tmp += last;
                last = 0;
            }
        } else {
            break;
        }
    }
    cout << tmp << '\n';
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    int _ = 1;
    cin >> _;
    while (_--) {
        solve();
    }
    return 0;
}
/*

1
3 1
3 3 3
8 1

 */