In this task, you need to count the number of words in a sentence that start with the given letter. Answer with numbers and not words.

Ex Input:
Sentence: 'a computer with a farm on the screen on top of a desk'. How many words start with the letter 'o' in the sentence.

Ex Output:
3


Ex Input:
Sentence: 'a man in a wheel chair holding a tennis racquet'. How many words start with the letter 't' in the sentence.

Ex Output:
1


Ex Input:
Sentence: 'a traffic light displays green against the backdrop of a large building with a clock'. How many words start with the letter 'b' in the sentence.

Ex Output:

2