Given a positive integer n, write a program to find out a nonzero multiple m of n whose decimal representation contains only the digits 0 and 1. You may assume that n is not greater than 200 and there is a corresponding m containing no more than 100 decimal digits.
Input The input file may contain multiple test cases. Each line contains a value of n (1 <= n <= 200). A line containing a zero terminates the input. Output For each value of n in the input print a line containing the corresponding value of m. The decimal representation of m must not contain more than 100 digits. If there are multiple solutions for a given value of n, any one of them is acceptable. Sample Input 2 6 19 0 Sample Output 10 100100100100100100 111111111111111111 #include <iostream> #include <cstdio> #include <cstring> using namespace std; int n,flag; void dfs(unsigned long long a,int step) { if(flag==1||step==19) { return ; } if(a%n==0) { printf("%I64u\n",a); flag=1; return ; } dfs(10*a,step+1); dfs(10*a+1,step+1); } int main() { while(~scanf("%d",&n)) { if(n==0) { break; } flag=0; dfs(1,0); } }