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
无符号长整才能过，怎么能这样
#include"iostream" using namespace std; typedef unsigned long long ll; int n; bool sign; void dfs(ll x,int cur) { if(sign) return ; if(x%n==0) { cout<<x<<endl; sign=true; return; } if(cur==19) return; dfs(x*10,cur+1); dfs(x*10+1,cur+1); } int main() { while(cin>>n&&n) { sign=false; dfs(1,0); } return 0; }