LeetCode in Kotlin
1781. Sum of Beauty of All Substrings
Medium
The beauty of a string is the difference in frequencies between the most frequent and least frequent characters.
- For example, the beauty of
"abaacc"is3 - 1 = 2.
Given a string s, return the sum of beauty of all of its substrings.
Example 1:
Input: s = “aabcb”
Output: 5
Explanation: The substrings with non-zero beauty are [“aab”,”aabc”,”aabcb”,”abcb”,”bcb”], each with beauty equal to 1.
Example 2:
Input: s = “aabcbaa”
Output: 17
Constraints:
1 <= s.length <= 500sconsists of only lowercase English letters.
Solution
class Solution {
fun beautySum(s: String): Int {
var beauty = 0
for (i in s.indices) {
val numCountOfFreq = IntArray(s.length + 1 - i)
val charFreq = IntArray(26)
charFreq[s[i].code - 'a'.code] = 1
numCountOfFreq[1] = 1
var min = 1
var max = 1
for (j in i + 1 until s.length) {
val c = s[j]
charFreq[c.code - 'a'.code]++
val freq = charFreq[c.code - 'a'.code]
numCountOfFreq[freq - 1]--
numCountOfFreq[freq]++
if (numCountOfFreq[min] == 0) {
min++
}
if (min > freq) {
min = freq
}
if (max < freq) {
max = freq
}
beauty += max - min
}
}
return beauty
}
}