#include <fstream>
#include <climits>

using namespace std;

ifstream f("sequencequery.in");
ofstream g("sequencequery.out");
int n,m,x,y,a[100001],b[100001],j,s,smax,i;
int main()
{
    smax=LONG_MAX;
    f>>n>>m;
    for (i=1;i<=n;i++)
    {
        f>>a[i];
    }
    b[1]=a[1];
    for (j=1;j<=m;j++)
    {
        f>>x>>y;
        smax=0;
        for (i=x;i<=y;i++)
        {
            b[i]=a[i];
        if (b[i-1]+a[i]>b[i])
        {
            b[i]=b[i-1]+a[i];
        }
        if (b[i]>smax)
        {
            smax=b[i];
        }
        }
        g<<smax<<" ";
    }
    return 0;
}