Answer: Python Puzzler #1647

The answer is A. The program prints:

52

Why?

The loop remembers the biggest number it has seen so far, and replaces it whenever it finds a bigger one. This is how computers find the maximum.

Trace table

A trace table follows the program step by step. Here’s this one:

n	n > biggest?	biggest
11	yes	11
22	yes	22
52	yes	52
16	no	52
5	no	52

The code again

numbers = [11, 22, 52, 16, 5]
biggest = 0
for n in numbers:
    if n > biggest:
        biggest = n
print(biggest)