1374. Generate a String With Characters That Have Odd Counts
Description
Given an integer n
, return a string with n
characters such that each character in such string occurs an odd number of times.
The returned string must contain only lowercase English letters. If there are multiples valid strings, return any of them.
Example 1:
Input: n = 4 Output: "pppz" Explanation: "pppz" is a valid string since the character 'p' occurs three times and the character 'z' occurs once. Note that there are many other valid strings such as "ohhh" and "love".
Example 2:
Input: n = 2 Output: "xy" Explanation: "xy" is a valid string since the characters 'x' and 'y' occur once. Note that there are many other valid strings such as "ag" and "ur".
Example 3:
Input: n = 7 Output: "holasss"
Constraints:
1 <= n <= 500
Solutions
Solution 1: Construction
If $n$ is odd, then we can directly construct a string with $n$ 'a'
characters.
If $n$ is even, then we can construct a string with $n-1$ 'a'
characters and $1$ 'b'
character.
The time complexity is $O(n)$, and the space complexity is $O(n)$. Where $n$ is the length of the string.
1 2 3 |
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1 2 3 4 5 |
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1 2 3 4 5 6 7 8 9 10 |
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1 2 3 4 5 6 7 8 9 |
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1 2 3 4 5 6 7 |
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