无限逼近思想

//#define LOCAL

#include<cstdio>

#include<algorithm>

using namespace std;

int const MAX_N=100001;

int const INF=10000000;

int N,M,x[MAX_N];

void init()

{

    for(int i=0;i<N;i++)

    {

        scanf("%d",&x[i]);

    }

}

//

bool C(int d)

{

    int last=0;

    for(int i=1;i<M;i++)

    {

        int crt=last+1;

        while(crt<N&&x[crt]-x[last]<d)

        {

            crt++;

        }

        if(crt==N) return false;

        last=crt;

    }

    return true;

}

void solve()

{

    //

    std::sort(x,x+N);

int lb=0,ub=INF;

    while(ub-lb>1)

    {

        int mid=(lb+ub)/2;

        if(C(mid)) lb=mid;

        else ub=mid;

    }

    printf("%d\n",lb);

}

int main()

{

#ifdef LOCAL

    freopen("1.in","r",stdin);

    freopen("1.out","w",stdout);

#endif

    while(~scanf("%d%d",&N,&M))

    {

        init();

        solve();

    }

    return 0;

}

无限逼近思想