HDU1755

 1 #include <cstdio>
 2 #include <cstring>
 3 #include <iostream>
 4 
 5 using namespace std;
 6 
 7 int vis[10] , n , m , x , k , num[10] , dp[102][102];
 8 const int INF = 1000000000;
 9 void dfs(int t , int state)
10 {
11     if(t >= n){
12         for(int i=1 ; i<=100;i++)
13             if(dp[i][state%i] > state)
14                 dp[i][state%i] = state;
15         return;
16     }
17     for(int i=0;i<n;i++){
18         if(!vis[i]){
19             vis[i] = 1;
20             dfs(t+1 , state*10+num[i]);
21             vis[i] = 0;
22         }
23     }
24 }
25 
26 int main()
27 {
28    // freopen("a.in","rb",stdin);
29     //cout<<10*9*8*7*6*5*4*3*2*1<<endl;
30     while(scanf("%d%d",&n,&m) == 2){
31         for(int i=0;i<n;i++)
32             scanf("%d",num+i);
33 
34         memset(vis,0,sizeof(vis));
35 
36         for(int i=0;i<=100;i++)
37             for(int j=0;j<=100;j++) dp[i][j] = INF;
38 
39         for(int i=0;i<n;i++){
40             if(num[i]){
41                 vis[i] = 1;
42                 dfs(1,num[i]);
43                 vis[i] = 0;
44             }
45         }
46         for(int i=0;i<m;i++)
47         {
48             scanf("%d%d",&x,&k);
49             if(dp[k][(((-x)%k)+k)%k] < INF)
50                 printf("%d\n",dp[k][(((-x)%k)+k)%k]); //state+x = b*k -> state%k = (-x)%k
51             else puts("None");
52         }
53     }
54     return 0;
55 }