#include "bits/stdc++.h"

typedef long long ll;

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

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

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

1
3 2
100 100 100
100 1
400 1

 */