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

Input: Consider Input: Sentence: 'a man with a large grey and black beard and glasses and a tie'. Find frequency of the letter 'e'

Output: 5


Input: Consider Input: Sentence: 'three birds are sitting on a tree in a forest'. Find frequency of the letter 'h'

Output: 1


Input: Consider Input: Sentence: 'a stadium of people watching a tennis game'. Find frequency of the letter 'i'


Output: 3