LeetCode in Kotlin
1663. Smallest String With A Given Numeric Value
Medium
The numeric value of a lowercase character is defined as its position (1-indexed) in the alphabet, so the numeric value of a is 1, the numeric value of b is 2, the numeric value of c is 3, and so on.
The numeric value of a string consisting of lowercase characters is defined as the sum of its characters’ numeric values. For example, the numeric value of the string "abe" is equal to 1 + 2 + 5 = 8.
You are given two integers n and k. Return the lexicographically smallest string with length equal to n and numeric value equal to k.
Note that a string x is lexicographically smaller than string y if x comes before y in dictionary order, that is, either x is a prefix of y, or if i is the first position such that x[i] != y[i], then x[i] comes before y[i] in alphabetic order.
Example 1:
Input: n = 3, k = 27
Output: “aay”
Explanation: The numeric value of the string is 1 + 1 + 25 = 27, and it is the smallest string with such a value and length equal to 3.
Example 2:
Input: n = 5, k = 73
Output: “aaszz”
Constraints:
1 <= n <= 105n <= k <= 26 * n
Solution
@Suppress("NAME_SHADOWING")
class Solution {
fun getSmallestString(n: Int, k: Int): String {
var n = n
var k = k
val res = CharArray(n)
res.fill('a')
k -= n
while (k > 0) {
--n
res[n] = res[n] + Math.min(25, k).toChar().code
k -= Math.min(25, k)
}
return String(res)
}
}