#include <iostream>
#include <fstream>
using namespace std;
ifstream f("tricouri.in");
ofstream g("tricouri.out");
long n,v[300000],i,aux,s;
int m,j,k,p;
int main ()
{
	f>>n>>m;
	for (i=1;i<=n;i++) f>>v[i];
	for (i=1;i<=n-1;i++) for (j=i+1;j<=n;j++) if (v[i]<v[j]) {aux=v[i];v[i]=v[j];v[j]=aux;}
	for (j=1;j<=m;j++) 
	{
		f>>k>>p;for (i=1;i<=k;i++) s+=v[i];
		while (s%p!=0)
			{
				s=s-v[i];
				s=s+v[i+1];
				i++;
				if (i==n) {s=-1;break;}
		    }
		g<<s<<'\n';
	}
	return 0;
	f.close();g.close();
}