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

Input: Consider Input: Sentence: 'a river with a long dragon boat in it and rowers on the boat in sets of two, along with two other people'. Find frequency of the letter 'h'

Output: 4


Input: Consider Input: Sentence: 'a man opening up a package sitting on a couch'. Find frequency of the letter 'n'

Output: 5


Input: Consider Input: Sentence: 'a pita pizza fills up an entire plate on a table'. Find frequency of the letter 'o'


Output: 1