ural 1640 Circle of Winter

 1 #include <cstdio>
 2 #include <cstring>
 3 #include <cmath>
 4 #include <algorithm>
 5 #define maxn 3000
 6 using namespace std;
 7 
 8 struct node
 9 {
10     int x,y;
11 }p[300];
12 double sqr(double x)
13 {
14     return x*x;
15 }
16 bool vis[maxn];
17 double dis(int x1,int y1,int x2,int y2)
18 {
19     return sqrt(sqr(x1-x2)+sqr(y1-y2));
20 }
21 int main()
22 {
23     int n;
24     scanf("%d",&n);
25     memset(vis,false,sizeof(vis));
26     for(int i=0; i<n; i++)
27     {
28         scanf("%d%d",&p[i].x,&p[i].y);
29         vis[p[i].x]=true;
30     }
31     int x,y;
32     for(int i=0; i<=maxn; i++)
33     {
34         if(!vis[i])
35         {
36             x=i;
37             y=0;
38             break;
39         }
40     }
41     double max1=-1;
42     for(int i=0; i<n; i++)
43     {
44         max1=max(max1,dis(p[i].x,p[i].y,x,y));
45     }
46     printf("%d %d %.9lf\n",x,y,max1);
47     return 0;
48 }