Day 32EasySmart Interviews (Hive)

Odd and Even Sum

Linear Scan + Modulo

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Problem

Problem Statement

Given an array of N integers, find the sum of all odd numbers and the sum of all even numbers separately.

Input / Output

Input:
  Line 1: Integer N
  Line 2: N space-separated integers

Output:
  Line 1: Sum of odd numbers
  Line 2: Sum of even numbers

Example:
  Input:  5
          1 2 3 4 5
  Output: 9
          6

Constraints

1 ≤ N ≤ 10^5
-10^9 ≤ arr[i] ≤ 10^9

Understanding the Problem

Check each number: is it odd or even?
Use modulo operator to determine parity
Add to the correct accumulator

Edge Cases

All even → odd_sum = 0
All odd → even_sum = 0
Negative numbers: Python -3 % 2 = 1 (odd ✅), Java -3 % 2 = -1 → use Math.abs(n % 2)

Solve it yourself before you look

Reading the solution first feels like progress, but it makes the next similar problem — and the interview version — much harder, because you skipped the part where you figure it out. Give it an honest 20–30 minutes. Stuck? Re-read the pattern, watch the concept video, or try the brute force first.

Hidden: approach · solution code