RMQ问题--ST

#include<iostream>
#include<cstdio>
#include<cmath>
using namespace std;
const int maxn = 1e5+5;
int f[maxn][25];
int n,m;
inline int RMQ(int l,int r){
    int k = log2(r-l+1);
    return min(f[l][k],f[r-(1<<k)+1][k]);
}
inline void ST(){
    for(int j = 1;j <= 20;j++)
        for(int i = 1;i <= n;i++)
            if(i+(1<<j)-1 <= n)
                f[i][j] = min(f[i][j-1],f[i+(1<<(j-1))][j-1]);
}
int main(){
    cin>>n>>m;
    for(int i = 1;i <= n;i++)
        scanf("%d",&f[i][0]);
    ST();
    for(int i = 1,x,y;i <= m;i++){
        scanf("%d%d",&x,&y);
        printf("%d ",RMQ(x,y));
    }
    return 0;
}

#include<iostream>
#include<cstdio>
using namespace std;
const int maxn = 1e5+5;
int a[maxn],f[maxn][25],log[maxn];
int n,m;
inline int RMQ(int l,int r){
    int k = log[r-l+1];
    return min(f[l][k],f[r-(1<<k)+1][k]);
}
inline void ST(){
    log[0] = -1;
    for(int i = 1;i <= n;i++){
        f[i][0] = a[i];
        log[i] = log[i>>1]+1;
    }
    for(int j = 1;j <= log[n];j++)
        for(int i = 1;(i+(1<<j)-1 <= n) && (i <= n);i++)
            f[i][j] = min(f[i][j-1],f[i+(1<<j-1)][j-1]);
}
int main(){
    cin>>n>>m;
    for(int i = 1;i <= n;i++)
        scanf("%d",&a[i]);
    ST();
    for(int i = 1,x,y;i <= m;i++){
        scanf("%d%d",&x,&y);
        printf("%d ",RMQ(x,y));
    }
    return 0;
}