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

void solve()
{
    int n, m;
    cin >> n >> m;

    vector<int> battery(n + 10),limit(n+10);
    vector<bool> vis(n+10);
    for (int i = 1; i <= n; i++) {
        cin >> battery[i];
        limit[i]=battery[i];
    }
    deque<int> dq;
    vector<pair<int, int>> v;
    for (int i = 1; i <= m; i++) {
        int loc, x;
        cin >> loc >> x;
        dq.push_back(x);
        vis[x]=1;
        v.push_back({loc, x});
    }
    for(int i=1;i<=n;i++) if(!vis[i]) dq.push_back(i);
    int now=dq.front(),x=0;
    int cnt = 0;
    for (int i = 0; i < m; i++) 
    {
        while(dq.size()&&x<v[i].first)
        {
            if(battery[now]>=v[i].first-x)
            {
                battery[now]-=v[i].first-x;
                x=v[i].first;
                break;
            }
            else
            {
                x+=battery[now];
                battery[now]=0;
                dq.pop_front();++cnt;
                if(dq.empty()) break;
                now=dq.front();
            }
        }
        // cerr << "**" << now << "**\n";
        if(x>=v[i].first)
        {
            battery[v[i].second]=limit[v[i].second];
            // cerr<<i<<"---"<<" "<<battery[v[i].second]<<endl;
            dq.push_back(v[i].second);
            while(cnt < i + 1) {
                dq.push_back(dq.front());
                dq.pop_front();
                ++cnt;
            }
            now = dq.front();
            // continue;
        }
        // cout<<i<<" "<<x<< " " << now <<  endl;
    }
    for(int i=1;i<=n;i++)
    {
        // cout<<i<<" "<<battery[i]<<endl;
        x+=battery[i];
    } 
    cout<<x<<endl;
}
signed main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    int T = 1;
    cin >> T;
    while (T--)
        solve();
    return 0;
}