#include<iostream>
#include<fstream>
#include<algorithm>
using namespace std;
ifstream fin("ssm.in");
ofstream fout("ssm.out");
int N,q,a,d[1005],v[1005]
int main()
{
    fin>>n>>q;
    for(int i=1; i<=n; i++)
    {
        fin>>v[i]
    }
    d[1]=v[1];
    for(int i=2; i<=n; i++)
    {
        d[i]=d[i-1]+v[i];
    }
    for
    int(int i=1; i<=q; i++)
    {
        fin>>a>>b;
        fout<<(d[b]-d[a-1])<<"\n";
    }
    return 0;
}