bus.py

# initialize 2d array
bus = [
    [0, 0, 0, 0],
    [0, 0, 0, 0],
    [0, 0, 0, 0],
    [0, 0, 0, 0],
]

# ask for reserved number
seat_number = int(input("Please the seat number you want to reserve: "))

# check for invalid choices
while seat_number <= 0 or seat_number > 16:
    print("Invalid seat number, must be in the interval [1, 16]")
    seat_number = int(input("Please pick again: "))

x, y = divmod(seat_number, 4)
name = input("Please enter your name: ")

for row in bus:
    for element in row:
        if element == name:
            name = input("Name taken, please enter another name: ")

bus[x - 1][y - 1] = name


payment = int(input("That would be P100, please enter your payment in pesos: "))
if payment < 100:
    print("Invalid payment payment should be > 100")
    payment = int(input("your payment: "))
else:
    print(f"Your change is {payment - 100}")
    print("Have a nice day!")

print(bus)