C program to find permutations of given strings

Suppose we have few strings in an array. We shall have to find all permutations of them in different line.

So, if the input is like strings = ["abc", "def", "ghi"], then the output will be

abc def ghi
abc ghi def
def abc ghi
def ghi abc
ghi abc def
ghi def abc

To solve this, we will follow these steps −

• Define a function next_permutation(), this will take n, string array s,
• for initialize i := n - 1, when i > 0, update (decrease i by 1), do:
  • if s[i] > s[i - 1]), then:
    • j := i + 1
  • for j
  • if s[j]
  • Come out from the loop
• t := s[i - 1]

Example

Let us see the following implementation to get better understanding −

#include 
#include 
int next_permutation(int n, char **s){
    for (int i = n - 1; i > 0; i--)
        if (strcmp(s[i], s[i - 1]) > 0){
            int j = i + 1;
            for (; j ' : ' ');
    } while (next_permutation(n, strings));
}

Input

{"abc", "def", "ghi"}

Output

abc def ghi
abc ghi def
def abc ghi
def ghi abc
ghi abc def
ghi def abc