007:Aggressive cows

输入样例

5 3
1
2
8
4
9

输出样例 

3

其实不难，普普通通二分查找。//但智障如我，数组开小了，还忘记注释重定向...

AC代码

#include <cmath>
#include <cstdio>
#include <cstring>
#include <iostream>
#include <algorithm>
using namespace std;
int a[110000]; int n, m; 
int isok(int d){
	int cnt = 0, tot = 1;
	for(int i = 1; i < n; ++i){
		if(a[i] - a[cnt] >= d){
			cnt = i, ++tot;
			if(tot >= m) return 1;
		}
	}
	return 0;
}
int main(){ 
	cin >> n >> m;  
	for(int i = 0; i < n; ++i) 	scanf("%d", &a[i]); 
	sort(a, a+n);
	int lef = 1, righ = a[n-1], mid = lef + (righ-lef)/2;
	while(righ - lef > 1){
		mid = lef + (righ-lef) / 2;
		if(isok(mid)) lef = mid;
		else righ = mid;
	} 
	cout << lef;
	return 0;
}