POJ1426——BFS——Find The Multiple

Description

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

Source

Dhaka 2002

大意：输入一个数，要求输出一个数满足是这个数的倍数，而且只由1和0构成，BFS用c++交超时，g++过了 (*@ο@*)

#include<cstdio>

#include<cstring>

#include<queue>

using namespace std;

queue <long long> q;

int n;

long long  bfs()

{

    while(!q.empty())

    q.pop();

    q.push(1);

    while(!q.empty()){

    long long p = q.front();

      q.pop();

      if(p%n == 0) return p;

      q.push(p*10);

      q.push(p*10+1);

    }

}

int main()

{

    while(~scanf("%d",&n)&&n){

            printf("%lld\n",bfs());

    }

    return 0;

}

View Code

 

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