#include<bits/stdc++.h>
#define LL long long
#define maxn 100010
using namespace std;

int t,n,m;
LL ans,sum,all;
int a[maxn],pos[maxn],id[maxn];

int main(){
	ios::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    
    cin>>t;
    while(t--){
    	cin>>n>>m;
		ans=0;pos[m+1]=0x7fffffff;sum=0;all=0;
    	for(int i=1;i<=n;i++) cin>>a[i],all+=a[i];
    	for(int i=1;i<=m;i++) cin>>pos[i]>>id[i];
    	for(int i=1;i<=m+1;i++){
    		if(pos[i]-pos[i-1]<=a[id[i]])
				ans+=pos[i]-pos[i-1];
    		else{
				ans+=a[id[i]];
	    		sum+=(pos[i]-pos[i-1])-a[id[i]];
	    		if(sum>=all-a[id[i]]){
	    			ans+=all;
				}
				sum-=a[id[i]];	
			}
		}
		cout<<ans<<endl;
	}
	return 0;
}