> #include <cmath>
> #include <cstdio>
> #include <cstring>
> #include <iostream>
> #include <algorithm>
> using namespace std;
> int n,i,j,k,l,flag;
> double M;
> struct node
> {
>     int x;
>     int y;
> } a[55];
> double cross(node T,node p,node q)
> {
>     return (p.x-T.x)*(q.y-T.y)-(p.y-T.y)*(q.x-T.x);
> }
> int temp[5];
> int main()
> {
>     char c;
>     while(scanf("%d",&n)&&n)
>     {
>         getchar();
>         for(int i=0; i<n; i++)
>         {
>             scanf("%c",&c);
>             scanf("%d%d",&a[i].x,&a[i].y);
>             getchar();
>         }
>         M=0.0;
>         memset(temp,0,sizeof(temp));
>         for(i=0; i<n; i++)
>         {
>             for(j=i+1; j<n; j++)
>             {
>                 for(k=j+1; k<n; k++)
>                 {
>                     flag=1;
>                     for(l=0; l<n; l++)
>                     {
>                         if(l!=i&&l!=j&&l!=k
>                                 &&cross(a[i],a[l],a[j])<=0
>                                 &&cross(a[j],a[l],a[k])<=0
>                                 &&cross(a[k],a[l],a[i])<=0)
>                         {
>                             flag=0;
>                             break;
>                         }
>                     }
>                     if(flag)
>                     {
>                         double s=0.5*fabs((a[i].x-a[k].x)*(a[j].y-a[k].y)-(a[i].y-a[k].y)*(a[j].x-a[k].x));
>                         if(s>M)
>                         {
>                             M=s;
>                             temp[1]=i;
>                             temp[2]=j;
>                             temp[3]=k;
>                         }
>                     }
>                 }
>             }
>         }
>         printf("%c%c%c\n",temp[1]+'A',temp[2]+'A',temp[3]+'A');
>     }
>     return 0;
> }

• Re:请大牛帮帮忙检查一下错在哪儿 (16) 14310120133 2016-04-08 19:13:41