部分和问题(dfs)

 1 #include<stdio.h>
 2 #include<stack>
 3 using namespace std;
 4 int m[21],n,k;
 5 stack<int>num;
 6 bool dfs(int temp,int i){
 7     if(i==n)return temp==k;
 8         if(dfs(temp,i+1))return true;
 9         if(dfs(temp+m[i],i+1)){
10             num.push(m[i]);
11             return true;
12         }
13     return false;
14 }
15 int main(){
16     while(~scanf("%d%d",&n,&k)){
17         for(int i=0;i<n;++i)scanf("%d",&m[i]);
18         if(dfs(0,0)){
19             printf("YES\n");
20             for(int i=0;!num.empty();i++){
21                 if(i)printf(" ");
22                 printf("%d",num.top());
23                 num.pop();
24             }
25             puts("");
26     }
27     else printf("NO\n");
28     }
29     return 0;
30 }