In this task, you need to count the number of times the given letter appears in the given sentence.

Input: Consider Input: Sentence: 'a scene at night; a plane alone on a runway with lit-up city buildings on the horizon'. Find frequency of the letter 'w'

Output: 2


Input: Consider Input: Sentence: 'a man standing on a surf board in the ocean'. Find frequency of the letter 'f'

Output: 1


Input: Consider Input: Sentence: 'a entertainment system on a wall of a living room'. Find frequency of the letter 't'


Output: 4