UVA-11636-Hello World!

 1 #include <iostream>
 2 #include<stdio.h>
 3 #include<stdlib.h>
 4 #include<string.h>
 5 #include<math.h>
 6 #include<algorithm>
 7 
 8 using namespace std;
 9 
10 int main()
11 {
12     int cnt=1,n,i,ans;
13     while(scanf("%d",&n)!=EOF&&n>=1)
14     {
15         printf("Case %d:",cnt++);
16         ans=0;
17         i=1;
18         while(i<=n)
19         {
20             i*=2;
21             ++ans;
22         }
23         if(i==n*2) --ans;
24         printf(" %d\n",ans);
25     }
26     return 0;
27 }