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 walking on a shore next to a river'. Find frequency of the letter 'v'

Output: 1


Input: Consider Input: Sentence: 'an elephant with broken tusks stands in front of a hill and boulders'. Find frequency of the letter 'n'

Output: 7


Input: Consider Input: Sentence: 'a hand is lifting a hotdog on a bun above a terrace ledge'. Find frequency of the letter 'e'


Output: 5