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

Input: Consider Input: Sentence: 'man in a sleeping bag on the floor using a laptop computer'. Find frequency of the letter 'i'

Output: 3


Input: Consider Input: Sentence: 'people playing wii bowling in a modern library'. Find frequency of the letter 'o'

Output: 3


Input: Consider Input: Sentence: 'a very spacious kitchen with the sun shining in the window'. Find frequency of the letter 'e'


Output: 4