#include <bits/stdc++.h>
using namespace std;
#define int long long

#define dbg(x...) \
do { \
std::cout << #x << " -> "; \
err(x); \
} while (0)

void err() {
	std::cout << std::endl;
}

template<class T, class... Ts>
void err(T arg, Ts &... args) {
	std::cout << fixed << setprecision(10) << arg << ' ';
	err(args...);
}

void GENSHEN_START() {
	int n,m;cin >> n >> m;
	vector <int> a(n + 1),b(n + 1);
	for (int i = 1;i <= n;i++) {
		cin >> a[i];
		b[i] = a[i];
	}
	vector <deque<int>> pos(n + 1); 
	vector <pair<int,int>> pi(m + 1);
	for (int i = 1;i <= m;i++) {
		cin >> pi[i].first >> pi[i].second;
		pos[pi[i].second].push_back(pi[i].first);
	}
	priority_queue<pair<int,int>,vector<pair<int,int>>,greater<>>q;
	for (int i = 1;i <= n;i++) {
		if (pos[i].size()) {
			//dbg(pos[i].front(),i);
			q.push({pos[i].front(),i});
		}
		else q.push({1e18,i});
	}
	int now = 0;
	for (int i = 1;i <= m;i++) {
		int dis = pi[i].first - now;
//		while (!q.empty() && q.top().first < pi[i].first) {
//			auto [p,w] = q.top();
//			pos[w].pop_front();
//			if (pos[w].size()) {
//				q.push({pos[w].front(),w});
//			}
//			else q.push({1e18,i});
//			q.pop();
//		}
		while (dis && !q.empty()) {
			auto [p,w] = q.top();
			if (dis > a[w]) {
				dis -= a[w];
				a[w] = 0;
				q.pop();
			}
			else {
				a[w] -= dis;
				dis = 0;
			}
		}
		if (q.empty()) {
			now = pi[i].first - dis;
			break;
		}
		if (q.top().first == pi[i].first && q.top().second == pi[i].second) q.pop();
		now = pi[i].first;
		a[pi[i].second] = b[pi[i].second];
		pos[pi[i].second].pop_front();
		if (pos[pi[i].second].size()) {
			q.push({pos[pi[i].second].front(),pi[i].second});
		}
		else q.push({1e18,i});
	}
	for (int i = 1;i <= n;i++) {
		now += a[i];
	}
	cout << now << '\n';
} 

signed main()
{
	ios::sync_with_stdio(false);cin.tie(nullptr);
	int T = 1;
	cin >> T;
	while (T--) GENSHEN_START();
	return 0;
}