poj 1426

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

26190

Sample Output

10100100100100100100111111111111111111

dfs搜索。
#include <iostream>using namespace std; int flag; void dfs(unsigned long long t,int n,int k) {   if(flag==1)    return ;   if(t%n==0)   {    cout<<t<<endl;    flag=1;    return ;   }   if(k==19)   return;   dfs(t*10,n,k+1);   dfs(t*10+1,n,k+1); }int main(){    int n;    while(cin>>n&&n!=0)    {     flag=0;    dfs(1,n,0);    }    return 0;}

k=20,就会爆内存