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

Input: Consider Input: Sentence: 'a river with a long dragon boat in it and rowers on the boat in sets of two, along with two other people'. Find frequency of the letter 'h'

Output: 4


Input: Consider Input: Sentence: 'a group of three dogs laying on a kitchen floor'. Find frequency of the letter 'r'

Output: 3


Input: Consider Input: Sentence: 'pedestrians and parked cars on a small village street'. Find frequency of the letter 'e'


Output: 6