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

Input: Consider Input: Sentence: 'an elephant has taken a man's hat in its trunk'. Find frequency of the letter 'p'

Output: 1


Input: Consider Input: Sentence: 'a yellow and green train on a train track in a wooded area'. Find frequency of the letter 'o'

Output: 4


Input: Consider Input: Sentence: 'the young boy is riding his snowboard on the mountain'. Find frequency of the letter 'n'


Output: 6