15.7 Tricky Cases

# Tricky if statements
ex_list = [1, 23, 421, 32]
if 1 == 2:
    for num in ex_list:
        print(num)
else:
    print(ex_list)

# Loops ending prematurely
ex_list = [1, 23, 421, 32]
counter = 0
for num in ex_list:
    counter += 1
    print(num)
    if counter == 1:
        break

When you first look at the code, you may think the running time is O(n) where n is the number of elements in the input list because of the for loop. However, the for loop ALWAYS iterates once regardless of the input because there is a break statement after counter is incremented by one. Since the for loop iterates once regardless of the input, the running time is O(1).