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Leetcode
Easy
Strings
Arrays
Longest Common Prefix

Find the longest prefix shared by every string in an array.

Acceptance 88%
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Problem Statement

Problem

Given an array of strings, return the longest prefix that appears at the start of every string.

If there is no common prefix, return an empty string.

A prefix is a substring that starts at the beginning of a string.

Notes

  • Compare the strings character by character from left to right.
  • The answer must be common to all strings, not just some of them.

Input Format

  • An array of strings strs.
  • strs[i] contains lowercase or mixed-case text depending on the platform variant.

Output Format

  • Return a single string: the longest common prefix across all strings in strs.

Constraints

  • 1 <= strs.length
  • Strings may be empty in some variants.
  • The answer length is at most the length of the shortest string.
Examples
Sample cases returned by the problem API.

Example 1

Input

strs = ["flower", "flow", "flight"]

Output

"fl"

Explanation

All three strings start with fl, but the next character differs.

Example 2

Input

strs = ["dog", "racecar", "car"]

Output

""

Explanation

There is no character sequence that appears at the start of every string.

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