fzu 1515 Balloons in a Box 【枚举】

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题目链接：https://vjudge.net/problem/FZU-1515
题意：给你一个立方体，立方体里有n个点，每个点代表一个圆心，你可以选择一个点开始扩充气球，知道碰到壁，或者碰到其他气球为止，问你立方体剩下的体积的最小值（四舍五入）
解析：挺水的一道题的，直接枚举就好，如果一个气球无法扩充可以跳过他，我也是莫名其妙wa了一版，还是自己太水了

#include <cstdio>#include <cstring>#include <algorithm>#include <cmath>#include <iostream>#include <vector>#include <queue>#include <set>using namespace std;const int maxn = 10;const double inf = 0x7ffffff;const double pi = acos(-1.0);struct point{    double x,y,z;    double r;}a[maxn],s,e;int n;double ans;double dis(point p1,point p2){    double tmp1 = (p1.x-p2.x)*(p1.x-p2.x);    double tmp2 = (p1.y-p2.y)*(p1.y-p2.y);    double tmp3 = (p1.z-p2.z)*(p1.z-p2.z);    return sqrt(tmp1+tmp2+tmp3);}double slove(int i){    double t1 = min(fabs(a[i].x-e.x),fabs(a[i].x-s.x));    double t2 = min(fabs(a[i].y-e.y),fabs(a[i].y-s.y));    double t3 = min(fabs(a[i].z-e.z),fabs(a[i].z-s.z));    double r = min(t1,t2);    r = min(t3,r);    return r;}double area(double r){    return 4.0*r*r*r*pi/3.0;}int main(){    while(~scanf("%d",&n))    {        scanf("%lf %lf %lf",&s.x,&s.y,&s.z);        scanf("%lf %lf %lf",&e.x,&e.y,&e.z);        double total = fabs((s.x-e.x)*(s.y-e.y)*(s.z-e.z));        memset(a,0,sizeof(a));        for(int i=0;i<n;i++)            scanf("%lf %lf %lf",&a[i].x,&a[i].y,&a[i].z);        double ans = 0;        int vis[maxn];        for(int i=0;i<n;i++)            vis[i] = i;        do        {            for(int i=0;i<n;i++)                a[i].r = 0;            double tmp = 0;            for(int i=0;i<n;i++)            {                a[vis[i]].r =slove(vis[i]);                for(int j=0;j<n;j++)                {                    if(i==j || a[vis[j]].r==0)                        continue;                    double tt = dis(a[vis[j]],a[vis[i]])-a[vis[j]].r;                    tt = max(tt,0.0);                    a[vis[i]].r = min(a[vis[i]].r,tt);                }                tmp += area(a[vis[i]].r);            }            ans = max(tmp,ans);        }while(next_permutation(vis,vis+n));        printf("%.0f\n",fabs(total-ans));    }    return 0;}/*20 0 010 10 103 3 37 7 7473 256 -38 -175 944 136-37 332 1-63 743 6448 472 -3235 753 386808 877 -957 661 329 -738763 572 -792687 539 -879673 795 -811679 500 -783717 545 -883667 629 -8257742776396816491870*/

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