LeetCode in Kotlin
3866. First Unique Even Element
Easy
You are given an integer array nums.
Return an integer denoting the first even integer (earliest by array index) that appears exactly once in nums. If no such integer exists, return -1.
An integer x is considered even if it is divisible by 2.
Example 1:
Input: nums = [3,4,2,5,4,6]
Output: 2
Explanation:
Both 2 and 6 are even and they appear exactly once. Since 2 occurs first in the array, the answer is 2.
Example 2:
Input: nums = [4,4]
Output: -1
Explanation:
No even integer appears exactly once, so return -1.
Constraints:
1 <= nums.length <= 1001 <= nums[i] <= 100
Solution
class Solution {
fun firstUniqueEven(nums: IntArray): Int {
val arr = IntArray(100)
for (num in nums) {
arr[num - 1]++
}
for (num in nums) {
if (num % 2 == 0 && (arr[num - 1] == 1)) {
return num
}
}
return -1
}
}