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

Input: Consider Input: Sentence: 'a picture of two computers on a table'. Find frequency of the letter 'r'

Output: 2


Input: Consider Input: Sentence: 'eight donuts are cooked together in oil in a metal tray'. Find frequency of the letter 'h'

Output: 2


Input: Consider Input: Sentence: 'a white red and yellow bus some motorcycles and cars'. Find frequency of the letter 'l'


Output: 3