Intermediate

itertools Module

The itertools module provides fast, memory-efficient tools for working with iterators and combinations.

Why Use itertools?

✔ Faster than manual loops
✔ Memory efficient
✔ Used in data processing & interviews

count()

from itertools import count

for i in count(10):
    if i > 15:
        break
    print(i)

cycle()

from itertools import cycle

colors = ["red", "green", "blue"]
for c in cycle(colors):
    print(c)
    break

combinations()

from itertools import combinations

nums = [1, 2, 3]
print(list(combinations(nums, 2)))

permutations()

from itertools import permutations

print(list(permutations([1, 2, 3], 2)))
📝 Practice: Generate all 3-letter passwords using itertools.
Next → functools Module