#include <bits/stdc++.h>
using namespace std;
const int N = 1e5 + 3;
int T;
int n, num;

typedef long long ll;
void work(){
	int n,m;cin >> n >> m;
	vector <ll> a(n);
	for(auto &x : a) cin >> x;
	vector <ll> c = a;
	vector <pair <ll,ll>> b(m);
	vector <vector <int>> p(n);
	for(int i = 0;i < m;i++) {
		cin >> b[i].first >> b[i].second;
		b[i].second -= 1;
		p[b[i].second].push_back(i);
	}
	ll sum = 0;
	set <int> st;
	for(int i = 0;i < n;i++) {
		if(p[i].size()) {
			reverse(p[i].begin(),p[i].end());
			st.insert(p[i].back());
		}else {
			sum += a[i];
			a[i] = 0;
		}
	}
	b.push_back({1e18,0});
	ll pos = 0;
	for(int i = 0;i < m;i++) {
		while(!st.empty()) {
			auto it = *st.begin();
//			cout << it << ' ';
			ll val = min(a[it],b[i].first - pos);
			pos += val;
			a[it] -= val;
			if(a[it]) break;
			st.erase(it);
		}
//		cout << pos << '\n';
		ll dis = min(b[i].first - pos,sum);
		pos += dis;
		sum -= dis;
		if(pos < b[i].first) break;
		int now = b[i].second;
		a[now] = c[now];
		p[now].pop_back();
		if(!p[now].empty()) st.insert({p[now].back()});
		else {
			sum += a[now];
			a[now] = 0;
		}
	}
//	for(int i = 0;i < n;i++) pos += a[i];
	cout << pos + sum << '\n';

}


int main(){
//	freopen("test.txt", "r", stdin);
	ios::sync_with_stdio(false);
	cin.tie(0);
	cin >> T;
	while(T--){
		work();
	}	
	return 0;
}