poj 3264 Balanced Lineup RMQ

emmm，第一遍的时候用的是C++的cin ，cout 果不其然，超时。

然后全部改为scanf和printf，卡过

#include <iostream>
#include <algorithm>
#include <cstdio>
#include <cmath>
using namespace std;

const  int maxn = 50005;
int a[maxn];
int n, m;
int minsum[maxn][50];
int maxsum[maxn][50];

void RMQ(int num) //预处理->O(nlogn)  
{
    //初始化
    for (int i = 1; i <= num; i++){
        minsum[i][0] = a[i];
        maxsum[i][0] = a[i];
    }

    for (int j = 1; j < 25; j++)
    for (int i = 1; i <= num; i++)
    if (i + (1 << j) - 1 <= num)
    {
        maxsum[i][j] = max(maxsum[i][j - 1], maxsum[i + (1 << (j - 1))][j - 1]);
        minsum[i][j] = min(minsum[i][j - 1], minsum[i + (1 << (j - 1))][j - 1]);
    }
}

//查询
int getmin(int x, int y){
    int k = (int)(log((double)(y - x + 1)) / log(2.0));
    return min(minsum[x][k], minsum[y - (1 << k) + 1][k]);
}

int getmax(int x, int y){
    int k = (int)(log((double)(y - x + 1)) / log(2.0));
    return max(maxsum[x][k], maxsum[y - (1 << k) + 1][k]);
}

int main(){
    scanf("%d%d", &n, &m);
    for (int i = 1; i <= n; i++){
        scanf("%d", &a[i]);
    }
    //预处理O(nlogn)
    RMQ(n);

    while (m--){
        int x, y;
        scanf("%d%d", &x, &y);
        int Min = getmin(x, y);
        int Max = getmax(x, y);
        int ans = Max - Min;
//        cout << "*" << Min << " " << Max << endl;
        printf("%d
", ans);
    }
    //system("pause");
    return 0;
}