DFS, anagrams

// test.cpp : Defines the entry point for the console application.///**数据结构练习*/  #include "stdafx.h"#include "stdlib.h"#include "stdio.h"#include <iostream>  #include <stack>  #include <vector>  #include "string"using namespace std;  string a,b;  stack<char> build;  vector<char> save;//容器，相当于动态数组  int len;  void dfs(int in,int out)///出入站的个数  {  if(in==len&&out==len)  {  for(int i=0;i<save.size();i++)  cout<<save[i]<<" ";cout<<"\n";  }  if(in<len)  {  build.push(a[in]);  save.push_back('i');  dfs(in+1,out);   // 深度优先进行遍历build.pop();     // 深度优先返回以后，恢复原状态save.pop_back();  }  if(out<in&&out<len&&build.top()==b[out]) // 深度优先返回后，进行其他情况考虑，就是考虑出栈  {  char _s=build.top();build.pop();  save.push_back('o');dfs(in,out+1);  build.push(_s);save.pop_back();  }  } int _tmain(int argc, _TCHAR* argv[]){while(cin>>a>>b)  {  len=a.length();  cout<<"["<<"\n";  dfs(0,0);  cout<<"]"<<"\n";  }  }