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

Ex Input:
Sentence: 'red chair next to side table with lamp in residential home'. Find frequency of the letter 'm'

Ex Output:
2


Ex Input:
Sentence: 'a couple of men standing inside of a liquor store'. Find frequency of the letter 'p'

Ex Output:
1


Ex Input:
Sentence: 'snowboarder and skiers on the snowy wooded slopes'. Find frequency of the letter 'o'

Ex Output:

7