/* 

You need to pass this function a vector containing characters that you want to 

get all permutations of, an integer which equals to 0, and empty vector.

then create a vector outside the function called 'allPermutations', and

it is gonna get filled up with all possible permutations, which will all be 

saved in vectors.

*/

#include <bits/stdc++.h>

using namespace std;

​

vector<vector<char>> allPermutations; // vector where you get all permutations

​

void perm(vector<char> vec,int curr,vector<char> currentPerm){

    if(currentPerm.size() == vec.size()){

        allPermutations.push_back(currentPerm);

        return;

    }

    char r = vec[curr];

    if(currentPerm.size() == 0){

        currentPerm.push_back(r);

        perm(vec,curr+1,currentPerm);

        return;

    }

    int cnt = 0;

    while(cnt <= currentPerm.size()){

        vector<char> temp;

        for(int i = 0; i < currentPerm.size(); i++){

            if(i == cnt)temp.push_back(r);

            temp.push_back(currentPerm[i]);

        }

        if(cnt == currentPerm.size())temp.push_back(r);

        perm(vec,curr+1,temp);

        cnt++;

    }

}

int main(){

  vector<char> vec = {'1','2','3','4'};

  vector<char> empty;

  perm(vec,0,empty);

  for(auto it : allPermutations){

      for(auto itt : it){

          cout << itt << " ";

      }

      cout << endl;

  }

}

#include <iostream>

#include <vector>

​

using namespace std;

​

void swap(int& a, int& b) {

    int temp = a;

    a = b;

    b = temp;

}

​

void generatePermutations(vector<int>& elements, int currentIndex) {

    if (currentIndex == elements.size() - 1) {

        for (int num : elements) {

            cout << num << " ";

        }

        cout << endl;

        return;

    }

​

    for (int i = currentIndex; i < elements.size(); ++i) {

        swap(elements[currentIndex], elements[i]);

        generatePermutations(elements, currentIndex + 1);

        swap(elements[currentIndex], elements[i]);

    }

}

​

int main() {

    vector<int> elements = {1, 2, 3}; // Replace this with the desired set of elements

    generatePermutations(elements, 0);

    return 0;

}