poj 3714 Raid 夜

#include<iostream>
#include<cstdio>
#include<string.h>
#include<algorithm>
#include<queue>
#include<vector>
#include<cmath>

using namespace std;
const double Max=2000000000.0;
struct node
{
    long x,y;
    bool k;
}mem[200005];
int M;
bool cmp(node a,node b)
{
    return a.x<b.x;
}
bool cmp1(node a,node b)
{
    return abs((a.y-M))<abs((b.y-M));
}
inline double L(int i,int j)
{
    if(mem[i].k==mem[j].k)
    {
        return Max;
    }
    long long x=(mem[i].x-mem[j].x);
    long long y=(mem[i].y-mem[j].y);
    return double (sqrt((x*x)+(y*y)));
}
double find(int I,int J)
{
    if(J-I==0)
    return Max;
    if(J-I==1)
    {
        return L(I,J);
    }
    int mid=(I+J)>>1;
    double an=min(find(I,mid),find(mid+1,J));
    int i,j;
    i=mid;
    while(i>=I&&mem[mid].x-mem[i].x<=an)
    {
        --i;
    }
    ++i;
    j=mid;
    while(j<=J&&mem[j].x-mem[mid].x<=an)
    ++j;
    --j;
    for(;i<=mid;++i)
    {
        M=mem[i].y;
        sort(mem+mid+1,mem+j+1,cmp1);
        for(int l=mid+1;l<=j&&l<=mid+6;++l)
        {
           an=min(an,L(i,l));
        }
    }
    sort(mem+mid+1,mem+j+1,cmp);
    return an;

}

int main()
{
    //freopen("data.txt","r",stdin);
    //freopen("A-large-practice.out","w",stdout);
    int T;
    int n;
    int i;
    scanf("%d",&T);
    while(T--)
    {
        scanf("%d",&n);
        for(i=1;i<=n;++i)
        {
            scanf("%ld %ld",&mem[i].x,&mem[i].y);
            mem[i].k=true;
        }
        for(;i<=2*n;++i)
        {
            scanf("%ld %ld",&mem[i].x,&mem[i].y);
            mem[i].k=false;
        }
        sort(mem+1,mem+1+2*n,cmp);
        printf("%.3f\n",find(1,2*n));

}
return 0;
}