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

Input: Consider Input: Sentence: 'a train sits on a railroad track as a metal awning covers it'. Find frequency of the letter 'l'

Output: 2


Input: Consider Input: Sentence: 'two people in a snowy place near a wooden fence'. Find frequency of the letter 'n'

Output: 5


Input: Consider Input: Sentence: 'a street sign that has been hit by cars'. Find frequency of the letter 'i'


Output: 2