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

Input: Consider Input: Sentence: 'a photo of a couple of people at a convention'. Find frequency of the letter 'v'

Output: 1


Input: Consider Input: Sentence: 'a plastic tray that has different foods inside of it'. Find frequency of the letter 't'

Output: 6


Input: Consider Input: Sentence: 'zebra graze on yellowed grass on a broad plane bordered by mountains'. Find frequency of the letter 'i'


Output: 1