#include <bits/stdc++.h>
using namespace std;
#define fastio ios::sync_with_stdio(false),cin.tie(0),cout.tie(0)
void test() {cerr << "\n";}
template<typename T, typename... Args> 
void test(T x, Args... args) {cerr << x << " ";test(args...);}
using ll = long long;
using ull = unsigned long long;



void solve(){
    int n,m;
    cin>>n>>m;
    vector<ll> a(n+1);
    ll sum = 0;
    for (int i=1;i<=n;i++){
        cin>>a[i];
        sum += a[i];
    }
    vector<array<ll,2>> ed;
    for (int i=0;i<m;i++){
        int a,b;
        cin>>a>>b;
        ed.push_back({a,b});
    }
    sort(ed.begin(),ed.end());
    ll des = 0;
    ll pre = 0;
    for (auto [u,v]:ed){
        if (des + u-pre>sum){
            break;
        }
        else{
            des += u-pre;
            des -= a[v];
            des=max(des,0ll);
        }
        pre=u;
    }
    pre += sum - des;
    cout<<pre<<"\n";
}



int main(){
    fastio;
    cout << fixed << setprecision(10);
    int T;
    cin>>T;

    while (T--){
        solve();
    }
    return 0;
}