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Leetcode
Easy
Math
Arrays
Count Odd Numbers In An Interval Range

Count how many odd integers lie in the inclusive range [low, high].

Acceptance 100%
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Problem Statement

Problem

Given two integers low and high, count how many odd numbers are in the inclusive interval [low, high].

An integer is odd if it is not divisible by 2.

Return the count of odd integers between low and high, including both endpoints.

Input Format

  • Two integers low and high describing an inclusive range.
  • low may be less than, equal to, or greater than high in generalized practice settings; assume valid interval ordering unless stated otherwise.

Output Format

  • Return a single integer: the number of odd integers in [low, high].

Constraints

  • The range endpoints are integers.
  • Use an approach that runs in constant time.
  • In standard interview settings, low <= high.
Examples
Sample cases returned by the problem API.

Example 1

Input

low = 3, high = 7

Output

3

Explanation

The odd numbers are 3, 5, and 7.

Example 2

Input

low = 8, high = 10

Output

1

Explanation

The only odd number in the range is 9.

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