Formatted question description: https://leetcode.ca/all/1523.html

# 1523. Count Odd Numbers in an Interval Range (Easy)

Given two non-negative integers `low`

and `high`

. Return the *count of odd numbers between *`low`

* and *`high`

* (inclusive)*.

**Example 1:**

Input:low = 3, high = 7Output:3Explanation:The odd numbers between 3 and 7 are [3,5,7].

**Example 2:**

Input:low = 8, high = 10Output:1Explanation:The odd numbers between 8 and 10 are [9].

**Constraints:**

`0 <= low <= high <= 10^9`

**Related Topics**:

Math

## Solution 1.

There are `high - low + 1`

numbers in the range, so there are at least `(high - low + 1) / 2`

odd numbers. If `low`

is odd, then there will be `(high - low + 1 + (low % 2)) / 2`

odd numbers.

```
// OJ: https://leetcode.com/problems/count-odd-numbers-in-an-interval-range/
// Time: O(1)
// Space: O(1)
class Solution {
public:
int countOdds(int low, int high) {
return (high - low + 1 + low % 2) / 2;
}
};
```

Java

```
class Solution {
public int countOdds(int low, int high) {
if (low % 2 == 0)
low++;
if (high % 2 == 0)
high--;
return (high - low) / 2 + 1;
}
}
```