学步园

#include <cstdio>
#include <cmath>
int main()
{
    int x,y;
    char c;
    double n,m;
    while(scanf("%d%c%d",&x,&c,&y)!=EOF)
    {
        if(x==0&&y==0)break;
        n=y*6.0;
        m=x*30.0+y/2.0;
        m=m-n;
        if(fabs(m)>180)m=360-fabs(m);
        printf("%.3lf\n",fabs(m));
    }
    return 0;
}