Given two integers a and b, return any string s such that:
s has length a + b and contains exactly a 'a' letters, and exactly b 'b' letters,'aaa' does not occur in s, and'bbb' does not occur in s.
Example 1:
Input: a = 1, b = 2 Output: "abb" Explanation: "abb", "bab" and "bba" are all correct answers.
Example 2:
Input: a = 4, b = 1 Output: "aabaa"
Constraints:
0 <= a, b <= 100s exists for the given a and b.This approach constructs the string by always choosing the majority character until we need to switch to prevent three consecutive characters.
Steps:
This C solution uses a static buffer result which is filled character by character based on the remaining count of 'a's and 'b's. The decision on whether to append 'a' or 'b' depends on the count of the last two characters, as well as the overall remaining count of 'a' and 'b'.
C++
Java
Python
C#
JavaScript
Time Complexity: O(a + b) because each character is processed once.
Space Complexity: O(a + b) for the result string.
This approach leverages an interleaving strategy to distribute characters evenly and avoid consecutive identical sequences.
Steps:
This C solution follows a clear pattern by interleaving the characters carefully based on their counts. It constructs the string by focusing on avoiding 'aaa' or 'bbb' through interleaving up to two of the more frequent characters with one of the weaker.
C++
Java
Python
C#
JavaScript
Time Complexity: O(a + b) due to iteration through characters.
Space Complexity: O(a + b) used for the output string.
| Approach | Complexity |
|---|---|
| Greedy Approach with Alternating Strategy | Time Complexity: O(a + b) because each character is processed once. |
| Interleaving Strategy | Time Complexity: O(a + b) due to iteration through characters. |
Longest Substring Without Repeating Characters - Leetcode 3 - Python • NeetCode • 657,697 views views
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