> #include <stdio.h>
> inline int abs(const int &a)
> { return a>0?a:-a; }
> int a,p,e,i,d,ans;
> int main()
> {
>     int ncase=1;
>     while(scanf("%d%d%d%d",&p,&e,&i,&d) && !(p==-1&&e==-1&&i==-1&&d==-1))
>     {
>         if(p==e && p==i)
>         {
>             ans = 21252 + e - d;
>             if(e>d)
>                 ans = e-d;
>             printf("Case %d: the next triple peak occurs in %d days.\n",ncase++,ans);
>             continue;
>         }    
>         for(a=(d-p)/23-1; a<=924; a++)
>             if((23*a+p>d && abs(23*a+p-e)%28==0 && abs(23*a+p-i)%33==0))
>                 break;
>         ans = 23 * a + p - d; 
>         if(ans>21252)
>             ans -= 21252;
>         if(ans<=0)
>             ans += 21252;
>         printf("Case %d: the next triple peak occurs in %d days.\n",ncase++,ans);
>     }  
>     return 0;
> }