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

Ex Input:
Sentence: 'man sitting on the side of a van playing the guitar'. Find frequency of the letter 'm'

Ex Output:
1


Ex Input:
Sentence: 'a bathroom with a sink, counter top, and mirror is shown'. Find frequency of the letter 'i'

Ex Output:
4


Ex Input:
Sentence: 'a woman wearing a dress holds a bottle'. Find frequency of the letter 'h'

Ex Output:

1