Practice/Google/Leetcode 1523. Count Odd Numbers in an Interval Range

Leetcode 1523. Count Odd Numbers in an Interval Range

CodingMust

Problem

Given two non-negative integers low and high, return the count of even integers in the inclusive range [low, high].

You must implement an efficient solution that works in constant time without iterating through the range, as the input values can be as large as 10^9.

Requirements

1. Count all even integers in the closed interval from low to high (inclusive)
2. Return the count as an integer
3. The solution must run in O(1) time complexity
4. Do not iterate through the range

Constraints

• 0 ≤ low ≤ high ≤ 10^9
• Both low and high are non-negative integers
• Time complexity: O(1)
• Space complexity: O(1)

Examples

Example 1:

Input: low = 3, high = 7 Output: 2 Explanation: The even numbers in the range are 4 and 6.

Example 2:

Input: low = 8, high = 10 Output: 2 Explanation: The even numbers in the range are 8 and 10.

Example 3:

Input: low = 4, high = 4 Output: 1 Explanation: The range contains only 4, which is even.

Example 4:

Input: low = 5, high = 5 Output: 0 Explanation: The range contains only 5, which is odd.