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

Input: Consider Input: Sentence: 'a little boy standing near a couch and a table'. Find frequency of the letter 'i'

Output: 2


Input: Consider Input: Sentence: 'a downhill skier with snow plumes behind them'. Find frequency of the letter 'i'

Output: 4


Input: Consider Input: Sentence: 'a zebra standing in the grass near trees'. Find frequency of the letter 't'


Output: 3