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

Input: Consider Input: Sentence: 'a gray colored pigeon that is perched on a railing outside of a building, with other buildings in the background'. Find frequency of the letter 'e'

Output: 7


Input: Consider Input: Sentence: 'a group of people standing around a table filled with assorted electronic devices'. Find frequency of the letter 'w'

Output: 1


Input: Consider Input: Sentence: 'colorful shapes and abstract art is displayed on a wall'. Find frequency of the letter 'i'


Output: 2