#include <bits/stdc++.h>
using namespace std;
#define int long long
#define sz(a) (int)(a.size())

signed main()
{
    int T;
    cin>>T;
    while(T--){
        int n, m;
        cin >> n >> m;
        int sum = 0;
        vector<int>a(n),x(m),t(m),d(m+1,4e18),cap(n);
        vector<deque<int>>charge(n);
        set<int>can;
        for(int i=0;i<n;i++)cin>>a[i];
        cap = a;

        for(int i=0;i<m;i++){
            cin>>x[i]>>t[i];
            t[i]--;
            charge[t[i]].push_back(i);
        }
        for(int i=0;i<n;i++){
            if(!charge[i].empty())can.insert(charge[i][0]);
        }

        for(int i=0;i<m;i++){
            if(!i)d[i] = x[i];
            else d[i] = x[i] - x[i-1];
        }

        int ans = 0;
        for(int i=0;i<m;i++){
            while(!can.empty() && d[i]){
                int id = t[*can.begin()];
                int mn = min(a[id],d[i]);
                d[i] -= mn;
                a[id] -= mn;
                ans += mn;

                if(!a[id])can.erase(can.begin());
            }
            int id = t[i];
            a[id] = cap[id];
            charge[id].pop_front();
            if(!charge[id].empty())can.insert(charge[id][0]);
            if(can.empty())break;
        }
        for(int i=0;i<n;i++)ans+=a[i];
        cout<<ans<<'\n';
    }
    return 0;

}