# [3216\. Lexicographically Smallest String After a Swap](https://leetcode.com/problems/lexicographically-smallest-string-after-a-swap/)

:::spoiler Hint

class Solution {
public:
    string getSmallestString(string s)
    {
        // Iterate through the string from the beginning to the second last character
        for ()
        {
            // Check if both current and next characters have the same parity (both even or both odd)
            // and if the current character is greater than the next character
            if ()
            {
                // Swap the current character with the next one
                // Exit the loop after the first swap
            }
        }
        // Return the modified string
    }
};

:::

:::spoiler Solution

class Solution {
public:
    string getSmallestString(string s)
    {
        for (int i = 0; i < s.size() - 1; ++i)
        {
            if (s[i] % 2 == s[i + 1] % 2 && s[i] > s[i + 1])
            {
                swap(s[i], s[i + 1]); break;
            }
        }
        return s;
    }
};

- 時間複雜度：$O(n)$
- 空間複雜度：$O(1)$
:::