Practice · 2 of 5
Choose the Team
CHALLENGE
Difficulty: intermediate+25 XP
**Description:** Count the ways to choose k people from n (order does not matter).
Compute C(n, k) exactly; the answer fits in 64 bits for these constraints
(1 <= k <= n <= 40).
**Input:** One line: n k (1 <= k <= n <= 40).
**Output:** One integer — C(n, k).
**Example:** 5 2 -> 10.
Press Submit to check your solution.
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