Count consonants in a string (Iterative and recursive methods)

Given a string, count total number of consonants in it. A consonant is an English alphabet character that is not vowel (a, e, i, o and u). Examples of constants are b, c, d, f, and g.

Examples : 

Input : abc de
Output : 3
There are three consonants b, c and d.

Input : geeksforgeeks portal
Output : 12

 1. Iterative Method 

3

Time Complexity: O(n), where n is the length of the string
Auxiliary Space: O(1)

 2. Recursive Method 

3

Time Complexity: O(n), where n is the length of the string
Auxiliary Space: O(n), due to recursive call stacks.

Illustration of recursive method:
 

👁 Image