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

Input: Consider Input: Sentence: 'a mixed bouquet of flowers in a glass vase set before a window'. Find frequency of the letter 'w'

Output: 3


Input: Consider Input: Sentence: 'salad and vegetables with me on top of plate'. Find frequency of the letter 'o'

Output: 3


Input: Consider Input: Sentence: 'there is a broken chair in front of the house'. Find frequency of the letter 'r'


Output: 4