Leetcode•Apr 16, 2025
Longest Common Prefix
Hazrat Ali
Leetcode
Write a function to find the longest common prefix string amongst an array of strings.
If there is no common prefix, return an empty string "".
Example 1:
Input: strs = ["flower","flow","flight"] Output: "fl"
Example 2:
Input: strs = ["dog","racecar","car"] Output: "" Explanation: There is no common prefix among the input strings.
Solution
/**
* @param {string[]} strs
* @return {string}
*/
const longestCommonPrefix = strs => {
if (!strs || strs.length === 0) {
return '';
}
for (let j = 0; j < strs[0].length; j++) {
for (let i = 1; i < strs.length; i++) {
if (j >= strs[i].length || strs[i][j] !== strs[0][j]) {
return strs[0].substring(0, j);
}
}
}
return strs[0];
};