LeetCode 2413. Smallest Even Multiple Java Solution

Problem

Smallest Even Multiple - LeetCode

Solution Approach

• The term "multiple of 2" indicates that the number must be even.
• The term "multiple of n" indicates that the number must be a multiple of n.
• This problem is about finding the smallest even multiple among the multiples of n.
• Initially, I attempted an algorithm where I iterated by incrementing n and returned it if it was even. However, I soon realized that the second multiple of n is always an even number.
• Therefore, the most efficient algorithm is as follows:
  • Check if n is even.
  • If n is even, return n.
  • If n is not even, then the next multiple will always be even.
  • Therefore, return n * 2.

Github Link

https://github.com/eunhanlee/LeetCode_2413_SmallestEvenMultiple_Solution.git

Time Complexity: O(1), Space Complexity: O(1)

public class Solution {
    /**
     * Finds the smallest even multiple of the given number.
     *
     * @param n The number for which the smallest even multiple needs to be found.
     * @return The smallest even multiple of the given number.
     */
    public int smallestEvenMultiple(int n) {
        if (n % 2 == 0) {
            return n;
        } else {
            return n * 2;
        }
    }
}