Control flow

Make decisions and repeat work with if, for and while.

Beginner 13 min read Lesson 2 of 480 Challenge included

What you will be able to do

Write if/elif/else chains
Loop over ranges and lists
Use break and continue

Control flow is how a program makes decisions and repeats work. Conditions are truthy or falsy; comparisons produce booleans.

control.pyPython

score = 78

if score >= 90:
    level = "excellent"
elif score >= 75:
    level = "passed"
else:
    level = "retry"

for day in range(1, 6):
    print(f"Study day {day}")

while score < 90:
    score += 2

break exits the loop immediately.
continue skips to the next iteration.
range(1, 6) yields 1 through 5 — the end is exclusive.

Your turn

FizzBuzz, briefly

Medium

Print numbers 1–15. For multiples of 3 print "Fizz", for 5 print "Buzz", for both print "FizzBuzz".

PYTHON · starter

for n in range(1, 16):
    # your code here
    pass

Check your understanding before moving on.

Knowledge checkQuestion 1

What does range(3) produce?

Select an answer to continue

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Lesson 2 of 480 · 0% of course