Solving Leetcode Interviews in Seconds with AI: Sort Vowels in a String
Introduction
In this blog post, we will explore how to solve the LeetCode problem "2785" using AI. LeetCode is a popular platform for preparing for coding interviews, and with the help of AI tools like Chatmagic, we can generate solutions quickly and efficiently - helping you pass the interviews and get the job offer without having to study for months.
Problem Statement
Given a 0-indexed string s, permute s to get a new string t such that: All consonants remain in their original places. More formally, if there is an index i with 0 <= i < s.length such that s[i] is a consonant, then t[i] = s[i]. The vowels must be sorted in the nondecreasing order of their ASCII values. More formally, for pairs of indices i, j with 0 <= i < j < s.length such that s[i] and s[j] are vowels, then t[i] must not have a higher ASCII value than t[j]. Return the resulting string. The vowels are 'a', 'e', 'i', 'o', and 'u', and they can appear in lowercase or uppercase. Consonants comprise all letters that are not vowels. Example 1: Input: s = "lEetcOde" Output: "lEOtcede" Explanation: 'E', 'O', and 'e' are the vowels in s; 'l', 't', 'c', and 'd' are all consonants. The vowels are sorted according to their ASCII values, and the consonants remain in the same places. Example 2: Input: s = "lYmpH" Output: "lYmpH" Explanation: There are no vowels in s (all characters in s are consonants), so we return "lYmpH". Constraints: 1 <= s.length <= 105 s consists only of letters of the English alphabet in uppercase and lowercase.
Explanation
Here's a breakdown of the solution:
- Identify and Separate: Iterate through the input string, separating vowels and consonants. Store the vowels in a separate list.
- Sort Vowels: Sort the extracted vowels list in ascending order based on their ASCII values.
Reconstruct String: Rebuild the string by iterating through the original string again. If a character is a consonant, place it directly in the new string. If it's a vowel, take the next sorted vowel and place it in the new string.
Runtime Complexity: O(n log n) due to the sorting of vowels, where n is the length of the string.
- Storage Complexity: O(n) because, in the worst case, we could have all vowels in the string which we store.
Code
def sort_vowels(s: str) -> str:
"""
Given a 0-indexed string s, permute s to get a new string t such that:
All consonants remain in their original places. More formally, if there is an index i with 0 <= i < s.length such that s[i] is a consonant, then t[i] = s[i].
The vowels must be sorted in the nondecreasing order of their ASCII values. More formally, for pairs of indices i, j with 0 <= i < j < s.length such that s[i] and s[j] are vowels, then t[i] must not have a higher ASCII value than t[j].
Return the resulting string.
The vowels are 'a', 'e', 'i', 'o', and 'u', and they can appear in lowercase or uppercase.
Consonants comprise all letters that are not vowels.
Example 1:
Input: s = "lEetcOde"
Output: "lEOtcede"
Explanation: 'E', 'O', and 'e' are the vowels in s; 'l', 't', 'c', and 'd' are all consonants. The vowels are sorted according to their ASCII values, and the consonants remain in the same places.
Example 2:
Input: s = "lYmpH"
Output: "lYmpH"
Explanation: There are no vowels in s (all characters in s are consonants), so we return "lYmpH".
Constraints:
1 <= s.length <= 105
s consists only of letters of the English alphabet in uppercase and lowercase.
"""
vowels = []
for char in s:
if char in "aeiouAEIOU":
vowels.append(char)
vowels.sort()
result = ""
vowel_index = 0
for char in s:
if char in "aeiouAEIOU":
result += vowels[vowel_index]
vowel_index += 1
else:
result += char
return result