1 /*************************************************************************
  2     > File Name: code/hdu/3552.cpp
  3     > Author: 111qqz
  4     > Email: rkz2013@126.com 
  5     > Created Time: 2015年11月09日 星期一 10时20分55秒
  6  ************************************************************************/
  7 
  8 #include<iostream>
  9 #include<iomanip>
 10 #include<cstdio>
 11 #include<algorithm>
 12 #include<cmath>
 13 #include<cstring>
 14 #include<string>
 15 #include<map>
 16 #include<set>
 17 #include<queue>
 18 #include<vector>
 19 #include<stack>
 20 #include<cctype>
 21 #define fst first              
 22 #define sec second      
 23 #define lson l,m,rt<<1
 24 #define rson m+1,r,rt<<1|1
 25 #define ms(a,x) memset(a,x,sizeof(a))
 26 using namespace std;
 27 const double eps = 1E-8;
 28 const int dx4[4]={1,0,0,-1};
 29 const int dy4[4]={0,-1,1,0};
 30 typedef long long LL;
 31 const int inf = 0x3f3f3f3f;
 32 const double pi = acos(-1.0);
 33 const int N=1E3+7;
 34 int n;
 35 double ang[N];
 36 int dblcmp( double d)
 37 {
 38     return d<-eps?-1:d>eps;
 39 }
 40 struct point
 41 {
 42     double x,y;
 43     point(){}
 44     point (double _x,double _y):
 45     x(_x),y(_y){};
 46 
 47     void input()
 48     {
 49     scanf("%lf %lf",&x,&y);
 50     }
 51 
 52     double myatan2(point p)
 53     {
 54     double res = atan2(p.y-y,p.x-x);
 55     return res>0?res:res+2*pi;
 56     }
 57 }p[N];
 58 
 59 int main()
 60 {
 61   #ifndef  ONLINE_JUDGE 
 62    freopen("in.txt","r",stdin);
 63   #endif
 64    
 65     while (scanf("%d",&n)!=EOF)
 66     {
 67     if (n<=0) break;
 68     for ( int i = 0 ; i < n ; i++) p[i].input();
 69     
 70         double mx = 0;
 71     for ( int i = 0 ; i < n ; i++ )
 72     {
 73         int cnt = 0 ;
 74         for ( int j = 0 ; j < n ;j++)
 75         {
 76         if (i==j) continue;
 77         ang[cnt++] = p[i].myatan2(p[j]);
 78         }
 79         sort(ang,ang+cnt);
 80         double mn = 999999;
 81         for ( int j = 0 ; j < cnt-1 ; j++)
 82         {
 83         double tmp = ang[j+1]-ang[j];
 84         if (dblcmp(tmp-pi)>0)   //直线的夹角不可能是钝角
 85         {
 86             tmp = 2*pi-tmp;
 87         }
 88         mn = min(tmp,mn);
 89         }
 90         mx = max(mn,mx);
 91     }
 92     printf("%.4f\n",mx*(180.0/pi));
 93 
 94     }
 95   
 96    
 97  #ifndef ONLINE_JUDGE  
 98   #endif
 99   fclose(stdin);
100     return 0;
101 }