Question $14$

Consider the following code snippet that generates all permutations of a given string:Which of the following statements is TRUE about the time complexity of this algorithm?The time complexity is O$($n$^2),$ where n is the length of the input string.The time complexity is O$($n$),$ where n is the length of the input string.The time complexity is O$(2^$n$),$ where n is the length of the input string.The time complexity is O$($n$!),$ where n is the length of the input string.