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Longest Palindromic Substring | Rulcode

122. Longest Palindromic Substring

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Example 1:

Input: s = "babad"

Output: "bab"

Explanation: The longest palindromic substring in "babad" is "bab". "aba" is also a valid answer.

Example 2:

Input: s = "cbbd"

Output: "bb"

Explanation: The longest palindromic substring in "cbbd" is "bb".

Example 3:

Input: s = "a"

Output: "a"

Explanation: If the input string has only one character, that character is the longest palindromic substring.

Example 4:

Input: s = "ac"

Output: "a"

Explanation: If there are no palindromic substrings of length greater than one, the first character is returned.

Constraints:

Time Complexity

O(n²)

Space Complexity

O(1)

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122. Longest Palindromic Substring

PRO

Medium

Topics

Companies

Hint

Understand Before Coding

Step 1 / 50

Speed: 1.0x

String Inspection

init mode

Process Step

Initialize max palindrome trackers: res = "" and resLen = 0.

Variables

index_iN/A

leftNone

rightNone

longest""

maxLen0

Loading visualization...

Visualize This Problem

Open Visualizer

Draw Your Approach

Draw

Example 1:

Input: s = "babad"

Output: "bab"

Explanation: The longest palindromic substring in "babad" is "bab". "aba" is also a valid answer.

Example 2:

Input: s = "cbbd"

Output: "bb"

Explanation: The longest palindromic substring in "cbbd" is "bb".

Example 3:

Input: s = "a"

Output: "a"

Explanation: If the input string has only one character, that character is the longest palindromic substring.

Example 4:

Input: s = "ac"

Output: "a"

Explanation: If there are no palindromic substrings of length greater than one, the first character is returned.

Constraints:

Time Complexity

O(n²)

Space Complexity

O(1)

Step 1 / 50

Speed: 1.0x

String Inspection

init mode

Process Step

Initialize max palindrome trackers: res = "" and resLen = 0.

Variables

index_iN/A

leftNone

rightNone

longest""

maxLen0

122. Longest Palindromic Substring

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Visualize This Problem

Draw Your Approach

Example 1:

Example 2:

Example 3:

Example 4:

Constraints:

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122. Longest Palindromic Substring

Understand Before Coding

String Inspection

Variables

Visualize This Problem

Draw Your Approach

Example 1:

Example 2:

Example 3:

Example 4:

Constraints:

Learn

Topics

Companies

Hint

Use Cases

String Inspection

Variables