1 #include <iostream> 2 #include <cstdio> 3 #include <cstring> 4 #include <algorithm> 5 using namespace std; 6 typedef long long LL; 7 const int maxn = 30; 8 char pre[maxn], in[maxn]; 9 void Build_PostTree(char *in, char *pre, int len) 10 { 11 if(!len) return; 12 int i = 0; 13 for( ; i < len; i++) 14 if(in[i] == *pre) break; 15 Build_PostTree(in, pre+1, i); //Left 16 Build_PostTree(in + i + 1, pre + i + 1, len - i - 1); // Right 17 cout << *pre; 18 return; 19 } 20 int main() 21 { 22 //freopen("in.txt","r",stdin); 23 while(scanf("%s %s", pre, in) != EOF){ 24 int len = strlen(pre); 25 Build_PostTree(in, pre, len); 26 cout << endl; 27 } 28 return 0; 29 }