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

Input: Consider Input: Sentence: 'a woman is taking a sip of a drink from a glass'. Find frequency of the letter 'i'

Output: 4


Input: Consider Input: Sentence: 'two pepperoni pizzas and a cup on a counter'. Find frequency of the letter 'u'

Output: 2


Input: Consider Input: Sentence: 'a double decker bus in london near some buildings'. Find frequency of the letter 'e'


Output: 5