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

Ex Input:
Sentence: 'eight donuts are cooked together in oil in a metal tray'. Find frequency of the letter 'h'

Ex Output:
2


Ex Input:
Sentence: 'one woman is arranging the other woman's hair'. Find frequency of the letter 'o'

Ex Output:
4


Ex Input:
Sentence: 'a woman floating in a  large blue pool of water'. Find frequency of the letter 'w'

Ex Output:

2