2012 ACM/ICPC Asia Regional Tianjin Online && hdu4279 Number

进制转换转换为8进制；；；

#include <cstdlib>
#include<cmath>
#include <iostream>
#include<algorithm>
#include<string.h>
using namespace std;
int main()
{
   // freopen("1.txt","w",stdout);
    long n,x,ans=0,xx;
	while(~scanf("%ld",&n)&&n)
	{
	  x=0;
	  xx=n;
	  char str[19];
	  ans=0;
	    int len;
		while(n/10)
		{
			sprintf(str,"%ld",n);
	       len=strlen(str)-1;
		   x=n/((long)pow(10.0,len));
		   if(x<3)ans+=x*((long) pow(8.0,len));
		   else if(x<8){ans+=(x-1)*((long)pow(8.0,len));}
		   else {
		    ans+=(x-2)*((long)pow(8.0,len));
		   }
		   n=n-x*((long)pow(10.0,len));
		}
		if(n<3)
			ans+=n;
		else if(n<8)ans+=(n-1);
		else
			ans+=(n-2);
		printf("%ld: %ld\n",xx,ans);
	}
    return 0;
}