LeetCode-in-Java
3216. Lexicographically Smallest String After a Swap
Easy
Given a string s containing only digits, return the lexicographically smallest string that can be obtained after swapping adjacent digits in s with the same parity at most once.
Digits have the same parity if both are odd or both are even. For example, 5 and 9, as well as 2 and 4, have the same parity, while 6 and 9 do not.
Example 1:
Input: s = “45320”
Output: “43520”
Explanation:
s[1] == '5' and s[2] == '3' both have the same parity, and swapping them results in the lexicographically smallest string.
Example 2:
Input: s = “001”
Output: “001”
Explanation:
There is no need to perform a swap because s is already the lexicographically smallest.
Constraints:
2 <= s.length <= 100sconsists only of digits.
Solution
public class Solution {
public String getSmallestString(String s) {
final char[] arr = s.toCharArray();
for (int i = 1; i < arr.length; i++) {
if (arr[i - 1] % 2 == arr[i] % 2 && arr[i - 1] > arr[i]) {
final char temp = arr[i];
arr[i] = arr[i - 1];
arr[i - 1] = temp;
break;
}
}
return String.valueOf(arr);
}
}