RMQ算法模板

#include <iostream>#include <cstdio>#include <cstdlib>#include <cstring>#include <cmath>#include <vector>#include <map>using namespace std;#define maxs( a , b ) a>b?a:b#define mins( a , b ) a>b?b:aconst int MAXN = 100005;int d[MAXN];int dpmin[MAXN][20];int dpmax[MAXN][20];int n;void create_Dpmin(){     int i , j;     for( i = 1 ; i <= n ; i++ )          dpmin[i][0] = d[i];     for( j = 1 ; j <= log((double)(n+1))/log(2.0) ; j++ ){          for( i = 1 ; i+(1<<j)-1 <= n ; i++ ){               dpmin[i][j] = mins( dpmin[i][j-1] , dpmin[i+(1<<(j-1))][j-1] );              }     }     }void create_Dpmax(){     int i , j;     for( i = 1 ; i <= n ; i++ )          dpmax[i][0] = d[i];     for( j = 1 ; j <= log((double)(n+1))/log(2.0) ; j++ ){          for( i = 1 ; i+(1<<j)-1 <= n ; i++ ){               dpmax[i][j] = maxs( dpmax[i][j-1] , dpmax[i+(1<<(j-1))][j-1] );              }     }     }int getmax( int a , int b ){    int k = (int)(log((double)(b-a+1))/log(2.0));    return maxs( dpmax[a][k] , dpmax[b-(1<<k)+1][k] );    }int getmin( int a , int b ){    int k = (int)(log((double)(b-a+1))/log(2.0));    return mins( dpmin[a][k] , dpmin[b-(1<<k)+1][k] );    }void Init(){     create_Dpmin();     create_Dpmax();     }int main(){       freopen( "in.txt" , "r" , stdin );    int T ;    string A, B;    for(scanf("%d", &T); T--;)    {    int i , m , a , b;    scanf("%d%d", &n, &m);    for( i = 1 ; i <= n ; i++ ){scanf("%d", &d[i]); // a为b的父亲    }    Init();    while( m-- ){           scanf("%d%d",&a,&b);                printf("%d\n",getmin(a,b)); //getmax(a, b)为找a, b中最大的那个数字。     }       }    return 0;    }