LeetCode in Kotlin
3184. Count Pairs That Form a Complete Day I
Easy
Given an integer array hours representing times in hours, return an integer denoting the number of pairs i, j where i < j and hours[i] + hours[j] forms a complete day.
A complete day is defined as a time duration that is an exact multiple of 24 hours.
For example, 1 day is 24 hours, 2 days is 48 hours, 3 days is 72 hours, and so on.
Example 1:
Input: hours = [12,12,30,24,24]
Output: 2
Explanation:
The pairs of indices that form a complete day are (0, 1) and (3, 4).
Example 2:
Input: hours = [72,48,24,3]
Output: 3
Explanation:
The pairs of indices that form a complete day are (0, 1), (0, 2), and (1, 2).
Constraints:
1 <= hours.length <= 1001 <= hours[i] <= 109
Solution
class Solution {
fun countCompleteDayPairs(hours: IntArray): Int {
val modular = IntArray(26)
var ans = 0
for (hour in hours) {
val mod = hour % 24
ans += modular[24 - mod]
if (mod == 0) {
modular[24]++
} else {
modular[mod]++
}
}
return ans
}
}