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Leetcode - 14. Longest Common Prefix

· One min read

https://leetcode.com/problems/longest-common-prefix/

Solution 1​

/**
 * @param {string[]} strs
 * @return {string}
 */
var longestCommonPrefix = function (strs) {
  if (strs.length === 1) {
    return strs[0];
  }

  const [baseWord, ...rest] = strs;

  for (let i = 0; i <= baseWord.length; i++) {
    for (let j = 0; j < strs.length; j++) {
      if (baseWord[i] !== strs[j][i]) {
        return baseWord.slice(0, i);
      }
    }
  }

  return baseWord;
};

Runtime: 116 ms, faster than 25.96% of JavaScript online submissions for Longest Common Prefix.

Memory Usage: 42.6 MB, less than 52.34% of JavaScript online submissions for Longest Common Prefix.

Solution 2​

/**
 * @param {string[]} strs
 * @return {string}
 */
var longestCommonPrefix = function (strs) {
  if (!strs.length) {
    return '';
  }

  for (let i = 0; i <= strs[0].length; i++) {
    if (!strs.every((string) => string[i] === strs[0][i])) {
      return strs[0].slice(0, i);
    }
  }

  return strs[0];
};

Runtime: 85 ms, faster than 77.67% of JavaScript online submissions for Longest Common Prefix.

Memory Usage: 43.1 MB, less than 34.02% of JavaScript online submissions for Longest Common Prefix.