RMQ

#include<iostream>
#include<cstring>
#include<cstdio>
#include<cstdlib>
#include<cmath>
#include<algorithm>
#include<ctime>
using namespace std;
const int N=1000005,M=25;
int n,m,a[N],f[N][M];
int query(int L,int R){
    int k;
    k=int(log(R-L+1)/log(2));
    return max(f[L][k],f[R+1-(1<<k)][k]);
}
int main(){
    int l,r;
    scanf("%d%d",&n,&m);
    for(int i=1;i<=n;i++){
        scanf("%d",&a[i]);
    }
    for(int i=1;i<=n;i++){
        f[i][0]=a[i];
    }
    for(int j=1;j<=int(log(n)/log(2));j++){
       for(int i=1;i+(1<<j)-1<=n;i++){
            f[i][j]=max(f[i][j-1],f[i+(1<<(j-1))][j-1]); 
       }
    }
    for(int i=1;i<=m;i++){
        scanf("%d%d",&l,&r);
        printf("%d\n",query(l,r));
    }
    return 0;
}