使用STL实现给定字符串的C++全排列

Input : s = “ADT”

Output : “ADT”, “ATD”, “DAT”, “DTA”, “TAD”, “TDA”

Explanation : In the given output as you can see all the string are made up of same three character present in our string and are just rearranged thus they fit in the definition of a permutation of a string now there is one more thing to note these are all the permutations possible of string s.

#include<bits/stdc++.h>
using namespace std;
void permutations(string s, string ans){
    if(s.size() == 0) {
// when our string which needs to
//be rotated becomes empty then it means
//that our permutation is stored in ans
        cout << ans << "\n";
        return ;
    }
    for(int i = 0; i < s.size(); i++){
        permutations(s.substr(1), ans + s[0]);
        // we are adding the
        // first character in our ans
        // passing all elements from index 1 in our
        // rotate string for next function.
        rotate(s.begin(), s.begin()+1, s.end());
        //rotating such that our second element becomes first
    }
}
int main(){
    string s = "ADT"; // given string
    permutations(s, "");
    return 0;
}

ADT
ATD
DTA
DAT
TAD
TDA

#include<bits/stdc++.h>
using namespace std;
int main(){
    string s = "ADT"; // given string
    sort(s.begin(), s.end()); // sorting the string
    do{
        cout << s << "\n"; // printing the permutations
    }while(next_permutation(s.begin(), s.end())); // till next_permutations returns false
    return 0;
}

ADT
ATD
DAT
DTA
TAD
TDA