In this task, you need to replace a letter in the sentence with another given letter.

Input: Consider Input: Sentence: 'a person is waiting for a pizza to come out of an oven fired grill'. Replace the letter 's' with 'k' in the sentence.

Output: a perkon ik waiting for a pizza to come out of an oven fired grill


Input: Consider Input: Sentence: 'a hipster riding a skateboard up the side of a wall'. Replace the letter 's' with 'm' in the sentence.

Output: a hipmter riding a mkateboard up the mide of a wall


Input: Consider Input: Sentence: 'a tour bus is empty on a downtown road'. Replace the letter 'd' with 'n' in the sentence.


Output: a tour bus is empty on a nowntown roan