BFS/poj 1426 Find The Multiple

 1 #include<cstdio>
 2 #include<cstring>
 3 #include<queue>
 4 using namespace std;
 5 int n;
 6 bool v[210];
 7 unsigned long long bfs(int n)
 8 {
 9     memset(v,0,sizeof(v));
10     queue<unsigned long long>que;
11     unsigned long long now,next;
12
13     now=1;v[1%n]=1;
14     que.push(now);
15
16     while (!que.empty())
17     {
18         now=que.front();
19         if (now%n==0) break;
20         que.pop();
21
22         next=now*10;
23         if (!v[next%n])
24         {
25             v[next%n]=1;
26             que.push(next);
27         }
28
29         next=now*10+1;
30         if (!v[next%n])
31         {
32             v[next%n]=1;
33             que.push(next);
34         }
35
36     }
37     return now;
38 }
39 int main()
40 {
41     scanf("%d",&n);
42     while (n!=0)
43     {
44         printf("%lld\n",bfs(n));
45         scanf("%d",&n);
46     }
47     return 0;
48 }