ZOJ2029 The Intervals，二分检索
题目说得很繁琐。。。就是给出一个集合A，对于给定的x，从A中选出两个元素beg, end作为一个半闭半开区间[beg, end)，这个区间要满足两个条件：1. x必须在[beg, end)中；2. [beg,end)长度最短。先对A排序，再二分检索答案。/******************************************************************************* # Author : Neo Fung # Email : neosfung@gmail.com # Last modified: 2012-07-04 19:33 # Filename: ZOJ2029 The Intervals.cpp # Description : ******************************************************************************/#ifdef _MSC_VER#define DEBUG#define _CRT_SECURE_NO_DEPRECATE#endif#include <fstream>#include <stdio.h>#include <iostream>#include <string.h>#include <string>#include <limits.h>#include <algorithm>#include <math.h>#include <numeric>#include <functional>#include <ctype.h>using namespace std;const int kMAX=10010;const double kEPS=10E-6;int n,m,num[kMAX];int BinSearch(const int &x){int l=0,r=n-1;if(x<num[l] || x>=num[r])return -1;while(l+1<r){int mid=(l+r)>>1;if(x<num[mid])r=mid;elsel=mid;}return l;}int main(void){#ifdef DEBUG freopen("../stdin.txt","r",stdin); freopen("../stdout.txt","w",stdout); #endif int tmp; while(~scanf("%d%d",&n,&m) ) {for(int i=0;i<n;++i)scanf("%d",&num[i]); sort(num,num+n);while(m--){scanf("%d",&tmp);int ans=BinSearch(tmp);if(ans>-1)printf("[%d,%d)\n",num[ans],num[ans+1]);elseprintf("no such interval\n");} puts(""); } return 0;}