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

Input: Consider Input: Sentence: 'four men standing around two pizzas in a conference room'. Find frequency of the letter 't'

Output: 2


Input: Consider Input: Sentence: 'two people under an umbrella while walking down a sidewalk'. Find frequency of the letter 'i'

Output: 3


Input: Consider Input: Sentence: 'a sandwich that is cut in half and sitting on a plate'. Find frequency of the letter 'n'


Output: 5