# bzoj1734 愤怒的牛

## Description

Farmer John has built a new long barn, with N (2 <= N <= 100,000) stalls. The stalls are located along a straight line at positions x1,...,xN (0 <= xi <= 1,000,000,000). His C (2 <= C <= N) cows don't like this barn layout and become aggressive towards each other once put into a stall. To prevent the cows from hurting each other, FJ want to assign the cows to the stalls, such that the minimum distance between any two of them is as large as possible. What is the largest minimum distance?

## Input

* Line 1: Two space-separated integers: N and C * Lines 2..N+1: Line i+1 contains an integer stall location, xi

## Output

* Line 1: One integer: the largest minimum distance

5 3
1
2
8
4
9

## Sample Output

3

#include<cstdio>
#include<algorithm>
using namespace std;
{
int x=0,f=1;char ch=getchar();
while(ch<'0'||ch>'9'){if(ch=='-')f=-1;ch=getchar();}
while(ch>='0'&&ch<='9'){x=x*10+ch-'0';ch=getchar();}
return x*f;
}
int n,m,ans,l,r;
int a[200001];
inline bool jud(int x)
{
int tot=1,now=1,save=1;
while (tot<=m)
{
while (a[now]-a[save]<x && now<=n) now++;
if (now>n && tot<m) return 0;
tot++;save=now;
if (tot==m) return 1;
}
return 1;
}
int main()
{
sort(a+1,a+n+1);
l=1;r=1000000000;
while (l<=r)
{
int mid=(l+r)>>1;
if (jud(mid)){ans=mid;l=mid+1;}
else r=mid-1;
}
printf("%d",ans);
}

posted @ 2016-08-20 22:45  ACforever  阅读(217)  评论(0编辑  收藏  举报