Added String Permutations for C++

string_permutations.cpp

@@ -0,0 +1,55 @@
+/*
+To find all possible permutation of letters in a given string
+fro e.g. abc
+abc
+acb
+bac
+bca
+cab
+cba
+TIME COMPLEXITY : O (n! * n)
+*/
+
+#include <iostream>
+#include <string.h>
+#include <ctype.h>
+#include <math.h>
+#include <stdio.h>
+#include <bits/stdc++.h>
+using namespace std;
+
+void perm(string s, int visited[], string &l, int &count)
+{
+    if (s.size() == l.size()) //Base case if generated string has same length as original string print it
+    {
+        count++; //add to count (total possible strings)
+        cout << l << endl;
+        return;
+    }
+    else
+    {
+        for (int i = 0; i < s.size(); i++)
+        {
+            if (visited[i] == 0) //if the character of string is not visited
+            {
+                visited[i] = 1;             //mark it as visited
+                l = l + s[i];               //append it to the generated string
+                perm(s, visited, l, count); //call perm function again
+                l.pop_back();               //pop the last element
+                visited[i] = 0;             //mark as unvisited
+            }
+        }
+    }
+}
+
+int main()
+{
+    string s, l = "";
+    cout << "\nEnter String :"; //take string from user
+    cin >> s;
+    int visited[s.size()] = {0}; //set all values of visited to 0
+    int count = 0;               //total possible strings
+    perm(s, visited, l, count);
+    cout << "\nTotal possible :" << count << endl;
+    return 0;
+}