#include<bits/stdc++.h>
using namespace std;
#define x first
#define y second
#define int long long
void solve(){
    int n,m;
    cin>>n>>m;
    vector<int> a(n+1),v(n+1),c(n+1),in(n+1);
    int sum=0;
    for(int i=1;i<=n;i++)cin>>a[i],sum+=a[i],in[i]=a[i];
    vector<pair<int,int>> b(m+1);
    deque<int> q;
    for(int i=1;i<=m;i++){
        cin>>b[i].x>>b[i].y;
        q.push_back(b[i].x);
        c[b[i].x]=1;
    }
    for(int i=1;i<=n;i++){
        if(!c[i])q.push_back(i);
    }
    int t=0,s=sum;
    for(int i=1;i<=m;i++){
        if(t+s>=b[i].x){
            int ne=b[i].x-b[i-1].x;
            while(ne&&q.size()&&a[q.front()]<=ne){
                s-=a[q.front()];
                ne-=a[q.front()];
                a[q.front()]=0;
                q.pop_front();
            }
            a[q.front()]-=ne;
            s-=ne;
            t=b[i].x;
            s+=in[b[i].y]-a[b[i].y];
        }
        else break;
    }
    t+=s;
    cout<<t<<"\n";
}
signed main(){
    cin.tie(0)->ios::sync_with_stdio(0);
    cout.tie(0);
    int t=1;
    cin>>t;
    while(t--)solve();
}