hdu 5443 (2015长春网赛G题 求区间最值)

求区间最值，数据范围也很小，因为只会线段树，所以套了线段树模板=.=

Sample Input
3
1
100
1
1 1
5
1 2 3 4 5
5
1 2
1 3
2 4
3 4
3 5
3
1 999999 1
4
1 1
1 2
2 3
3 3

Sample Output
100
2
3
4
4
5
1
999999
999999
1

 # include <iostream>
 # include <cstdio>
 # include <cstring>
 # include <algorithm>
 # include <cmath>
 # include <queue>
 # define LL long long
 using namespace std ;

 const int maxn = ;

 int MAX[maxn<<] ; //结点开4倍

 void PushUP(int rt) //更新到父节点
 {
     MAX[rt] = max(MAX[rt * ] , MAX[rt *  + ] ); //rt 为当前结点
 }

 void build(int l , int r , int rt) //构建线段树
 {
     if (l == r)
     {
         scanf("%d" , &MAX[rt]) ;
         return ;
     }
     int m = (l + r) /  ;
     build(l , m , rt * ) ;
     build(m +  , r , rt *  +) ;
     PushUP(rt) ;
 }

 int query(int L , int R , int l , int r , int rt)  //区间求最大值
 {
     if (L <= l && r <= R)
         return MAX[rt] ;
     int m = (l + r) /  ;
     int ret =  ;
     if (L <= m)
        ret = max(ret , query(L , R , l , m , rt * ) ) ;
     if (R > m)
        ret = max(ret , query(L , R , m +  , r , rt *  + ) );
     return ret ;
 }

 int main ()
 {
     //freopen("in.txt","r",stdin) ;
     int n , m ;
     int T ;
     scanf("%d" , &T) ;
     while(T--)
     {
         scanf("%d" , &n) ;
         build( , n , ) ;
         scanf("%d" , &m) ;
         while(m--)
         {
             int a , b ;
             scanf("%d %d" , &a , &b) ;
             printf("%d\n", query(a , b ,  , n , ))  ;
         }
     }

     return  ;
 }