HDU 4403 A very hard Aoshu problem（dfs爆搜）

 1 #include<iostream>
 2 #include<cstdio>
 3 #include<cstring>
 4 #include<algorithm>
 5 #include<map>
 6 using namespace std;
 7 
 8 char s[20];
 9 int a[2][100], tot[2], ans;
10 map<int,int> f;
11 
12 void dfs(int cur, int pre, int sum, int ends, int id)
13 {
14     if(cur == ends)
15     {
16         if(pre)  return;
17         if(!id)  f[sum]++;
18         else if(f[sum])  ans+=f[sum];
19         return;
20     }
21     dfs(cur+1,0,sum+pre*10+s[cur]-‘0‘,ends,id);
22     dfs(cur+1,pre*10+s[cur]-‘0‘,sum,ends,id);
23 }
24 
25 int main()
26 {
27     //freopen("in.txt","r",stdin);
28     while(~scanf("%s",s) && s[0]!=‘E‘)
29     {
30         ans = 0;
31         int n = strlen(s);
32         for(int i=1;i<n;i++)
33         {
34             f.clear();
35             dfs(0,0,0,i,0);
36             dfs(i,0,0,n,1);
37         }
38         printf("%d\n",ans);
39     }
40 }