#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<int> vis(n+10);
    for (int i = 1; i <= n; i++) 
    {
        cin >> battery[i];
        limit[i]=battery[i];
    }
    vector<pair<int, int>> v;
    queue<int> q1,q2;
    for (int i = 1; i <= m; i++) 
    {
        int loc, x;
        cin >> loc >> x;
        vis[x]++;
        q1.push(x);
        v.push_back({loc, x});
    }
    for(int i=1;i<=n;i++) if(!vis[i]) q2.push(i);
    int x=0;
    for(int i=0;i<m;i++)
    {
        int d=v[i].first,id=v[i].second;
        // cout<<i<<"+++++"<<x<<endl;
        while(q1.size())
        {
            int k=q1.front();
            q1.pop();
            // cout<<k<<"---\n";
            if(!battery[k])
            {
                if(--vis[k]==0) q2.push(k);
            }
            if(battery[k]>=d-x) 
            {
                battery[k]-=d-x;
                x=d;
                break;
            }
            else
            {
                x+=battery[k];
                battery[k]=0;
            }
        }
        if(x==d) 
        {
            battery[id]=limit[id];
            if(vis[id]) q1.push(id);
        }
        else
        {
            while(q2.size())
            {
                int k=q2.front();
                // cout<<k<<"+++\n";
                if(battery[k]>=d-x) 
                {
                    // cout<<k<<"***"<<battery[k]<<endl;
                    battery[k]-=d-x;
                    x=d;
                    if(!battery[k]) q2.pop();
                    break;
                }
                else
                {
                    x+=battery[k];
                    battery[k]=0;
                    q2.pop();
                } 
            }
            if(x==d) 
            {
                battery[id]=limit[id];
                if(vis[id]) q1.push(id);
            }
            else break;
        }
        // cout<<i<<"----"<<x<<endl;
    }
    // cout<<x<<endl;
    for(int i=1;i<=n;i++) 
    {
        // cout<<i<<" "<<battery[i]<<endl;
        x+=battery[i];
    }
    cout<<x<<endl;
    return ;
}
signed main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    int T = 1;
    cin >> T;
    while (T--)
        solve();
    return 0;
}