1 #include <iostream> 2 #include <string> 3 using namespace std; 4  5 string pr,in; 6 string postorder; 7 void process(string preord,string inord); 8 int main() 9 {10     int line,order;11     //freopen("D:\\acm.txt","r",stdin);12     cin>>line;13     while(line--){14         cin>>order;15         cin>>pr>>in;16         postorder.clear();17         process(pr,in);18         cout<<postorder<<endl;19     }20     return 0;21 }22 void process(string preord,string inord){23     int Size = preord.size();24     if(Size>0){25         int p = inord.find(preord[0]);26         process(preord.substr(1,p),inord.substr(0,p));//左树27         process(preord.substr(p + 1,Size - (p + 1)),inord.substr(p + 1,Size - (p + 1)));//右树28         postorder.push_back(preord[0]);29     }30 }