#include <stdio.h>
#include <algorithm>
#include <vector>
#include <map>
using namespace std;
map<int, int> chk;
int N,Q,C,X[100010],O[100010],Z,F; long long R[100010],B[200100],A[100010];
struct seg{
seg(int s_, int e_, int i_){s = s_; e = e_; i = i_;}
int s,e,i;
bool operator <(const seg t)const{return e != t.e ? e < t.e : s < t.s;}
};
vector<seg> intv[201];
void upt(int x, int p)
{
x = X[x]; O[x] += p;
B[x+F] = R[x] * O[x];
x = (x + F + 2) / 4;
while (x){
B[x] = max(max(B[x*4-2],B[x*4-1]),max(B[x*4],B[x*4+1]));
x = (x + 2) / 4;
}
}
int main()
{
scanf ("%d %d",&N,&Q);
for (int i=0;i<N;i++){
scanf ("%d",&X[i]);
chk[X[i]] = 0;
}
for (map<int, int>::iterator I = chk.begin(); I != chk.end(); I++) R[C] = I->first, I->second = C++;
for (int i=0;i<N;i++) X[i] = chk[X[i]];
for (Z=1;Z<C;Z<<=2) F += Z; F++;
for (int i=0,s,e;i<Q;i++){
scanf ("%d %d",&s,&e); s--;
intv[s/10000].push_back(seg(s,e,i));
}
for (int i=0;i<10;i++) if (!intv[i].empty()){
for (int k=0;k<F+C;k++) B[k] = 0;
for (int k=0;k<C;k++) O[k] = 0;
int s = 0, e = 0;
sort(intv[i].begin(),intv[i].end());
for (int j=0;j<intv[i].size();j++){
while (e < intv[i][j].e) upt(e++,1);
while (s < intv[i][j].s) upt(s++,-1);
while (s > intv[i][j].s) upt(--s,1);
A[intv[i][j].i] = B[1];
}
}
for (int i=0;i<Q;i++) printf ("%lld\n",A[i]);
return 0;
}
