Level 5Exercise #114

Count values in a range

Count sorted values between low and high, inclusive, in O(log n).

What you’ll practice

This Level 5 exercise focuses on bisect bounds in the Algorithms curriculum. Solve the challenge prompt above using clear, idiomatic Python and the relevant language or standard-library tools.

Relevant Python reference: bisect — Array bisection algorithm.

Sample Test Cases

Example #1

Input:count_between([1,2,2,4,7], low=2, high=4)

Output:3

Reference Solution

Reveal Reference Solution

def count_between(values: list[int], low: int, high: int) -> int:
    from bisect import bisect_left, bisect_right
    return bisect_right(values, high) - bisect_left(values, low)

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Count values in a range

What you’ll practice

Sample Test Cases

Further Reading

Reference Solution