Python Fundamentals / Loops
Lesson 20 of 38
Nested loops
A loop inside a loop runs the inner loop fully for every round of the outer one. Great for grids and tables.
Key points
- Inner loop runs completely each time
- 3 outer x 4 inner = 12 runs
- Watch out for slow code with big nested loops
for row in range(3):
for col in range(3):
print("#", end="")
print()Quiz · +10 XP
An outer loop runs 4 times and an inner loop 5 times. How many inner runs in total?
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