【模板】RMQ

#include<iostream>
#include<cstdio>
#include<cstring>
#include<cmath>
using namespace std;
const int N=100010;
int n,m,l;
int a[N],f[N][20];
int main(){
//  freopen("in.txt","r",stdin);
//  freopen("out.txt","w",stdout);
    scanf("%d%d",&n,&m);
    for(int i=1;i<=n;i++) {
        scanf("%d",&a[i]);
        f[i][0]=a[i];
//      printf("%d %d %d\n",i,0,f[i][0]);
    }
    l=(int)((double)log(n)/(double)log(2));
    for(int i=1;i<=l;i++)
        for(int j=1;j<=n-(1<<i)+1;j++){
            f[j][i]=min(f[j][i-1],f[j+(1<<(i-1))][i-1]);
//          printf("%d %d %d\n",j,i,f[j][i]);
        }
    for(int i=1;i<=m;i++){
        int x,y;
        scanf("%d%d",&x,&y);
        l=(int)((double)log(y-x+1)/(double)log(2));
        int ans=min(f[x][l],f[y-(1<<l)+1][l]);
        printf("%d\n",ans);
    }
    return 0;
}