575 - Skew Binary

#include<stdio.h>#include<string.h>#include<math.h>int main(void){char a[1000]={0};while(gets(a)){if(strlen(a)==1&&a[0]=='0') break;long i,sum=0;for(i=0;i<strlen(a);i++)sum+=(a[i]-'0')*(pow(2,strlen(a)-i)-1);printf("%ld\n",sum);}return 0;}