SWUST OJ 0032 简单的背包 解题报告

 1 #include<stdio.h>
 2 int w[100],s,n,x,book[100];
 3 void dfs(int weight)
 4 {
 5     int i;
 6     if(weight==s)x++;
 7     if(weight>s)return ;
 8     for(i=1;i<=n;i++)
 9     {
10         if(book[i]==0)
11         {
12         book[i]=1;
13         dfs(weight+w[i]);
14         book[i]=0;
15         }
16     }
17 }
18 int main()
19 {
20     int i;
21     while(scanf("%d %d",&s,&n)!=EOF)
22     {
23     for(i=1;i<=n;i++)
24     {
25         scanf("%d",&w[i]);
26     }
27     dfs(0);
28     if(x>0)printf("YES\n");
29     else printf("NO\n");
30     x=0;
31     }
32     return 0;
33 }