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

Input: Consider Input: Sentence: 'a girl sits on a surfboard and smiles'. Find frequency of the letter 'i'

Output: 3


Input: Consider Input: Sentence: 'a truck is parked in front of a store'. Find frequency of the letter 't'

Output: 3


Input: Consider Input: Sentence: 'hotel towels with sunglasses perched and hotel business cards and catalog'. Find frequency of the letter 'o'


Output: 4