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

Input: Consider Input: Sentence: 'a man that is on his cell phone'. Find frequency of the letter 's'

Output: 2


Input: Consider Input: Sentence: 'man in air skateboarding on street with building'. Find frequency of the letter 't'

Output: 4


Input: Consider Input: Sentence: 'a woman holds tape and scissors close to the camera'. Find frequency of the letter 'r'


Output: 2