使用DFS生成全排列

 1 #include <string>

 2 #include <cstdio>

 3 #include <cstdlib>

 4 #include <iostream>

 5 #include <algorithm>

 6 

 7 using namespace std;

 8 

 9 // 使用DFS深度优先搜索生成全排列

10 // 如果当前生成的排列满足条件（逻辑意义上的有序），返回true

11 bool dfs(string &bunch, int bLen, string str) {

12     if (bLen == str.length()) {

13             // 

14     }

15     

16     string::size_type i;

17     for (i = 0; i < bLen; ++i) {

18         if (!vis[i]) {

19             vis[i] = true;

20             str += bunch[i];

21             if (dfs(bunch, bLen, str)) {

22                 return true;

23             }

24             vis[i] = false;

25             str = str.substr(0, str.length() - 1);

26         }

27     }// End of for

28     return false;

29 }

30 

31 int main() {

32     string bunch;

33     

34     while (cin >> bunch) {

35         dfs(bunch, bunch.length(), "");

36     }// End of while

37     return 0;

38 }

方法二：使用STL中的next_permutation生成

 1 #include <string>

 2 #include <cstdio>

 3 #include <cstdlib>

 4 #include <iostream>

 5 #include <algorithm>

 6 

 7 using namespace std;

 8 

 9 string res;

10 

11 int main() {

12     string bunch;

13     

14     while (cin >> bunch) {

15         sort(bunch.begin(), bunch.end());

16         do {

17             cout << bunch << endl;

18         } while (next_permutation(bunch.begin(), bunch.end()));

19     }// End of while

20     return 0;

21 }