> #include"stdio.h"
> double qwe(int x,int y)
> 	{double sum=1.0;
> if(x==y)return 1.0;
> 	while(1)
> 		{sum=sum*x;
> 		x--;
> 		if(x==y)break;
> 		}
> return sum;
> 	}
> double shu(int p,int q,int r,int s)
> {double m=1.0,n=1.0;
> 
> if(q>r||s>p||p==q||r==s){m*=qwe(p,q);n=qwe(r,s);}
> else{ if(p>r)m*=qwe(p,r);
> 	 else {if(p-r<0)n=qwe(r,p);}
>       if(q-s>0)n*=qwe(q,s);
>       else {if(s-q>0)m*=qwe(s,q);}
> 	}
>       if((p-q)-(r-s)>0)n*=qwe(p-q,r-s);
>        else {if((p-q)-(r-s)<0)m*=qwe(r-s,p-q);}
> 
> return m/n;
> }
> 
> void main()
> {double shu(int p,int q,int r,int s);
> 	int p,q,r,s,i;
> double a[6];
> for(i=0;i<6;i++)
> 	{scanf("%d%d%d%d",&p,&q,&r,&s);
> 	 a[i]=shu(p,q,r,s);
> 	}
> for(i=0;i<6;i++)
> printf("%.5lf\n",a[i]);
> 
> }