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

Input: Consider Input: Sentence: 'a baby elephant walks beside an adult elephant along a post and cable'. Find frequency of the letter 'l'

Output: 6


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

Output: 4


Input: Consider Input: Sentence: 'a cutting board with chopped celery , onions, and carrots on it'. Find frequency of the letter 'n'


Output: 5