14. Longest Common Prefix

[Tcdian]

14. Longest Common Prefix

编写一个函数来查找字符串数组中的最长公共前缀。

如果不存在公共前缀，返回空字符串 ""。

Example 1

Input: ["flower","flow","flight"]
Output: "fl"

Example 2

Input: ["dog","racecar","car"]
Output: ""
Explanation: There is no common prefix among the input strings.

Note

• 所有输入只包含小写字母 a-z 。

[Tcdian]

Solution

• JavaScript Solution

/**
 * @param {string[]} strs
 * @return {string}
 */
var longestCommonPrefix = function(strs) {
    if (strs.length === 0) {
        return '';
    }
    const firstStr = strs[0];
    let prefix = '';
    for (let i = 0; i < firstStr.length; i++) {
        let letter = firstStr[i];
        for (let j = 1; j < strs.length; j++) {
            if (strs[j][i] !== letter) {
                letter = '';
                break;
            }
        }
        if (letter !== '') {
            prefix += letter;
        } else {a
            break;
        }
    }
    return prefix;
};

• TypeScript Solution

function longestCommonPrefix(strs: string[]): string {
    if (strs.length === 0) {
        return '';
    }
    const firstStr = strs[0];
    let prefix = '';
    for (let i = 0; i < firstStr.length; i++) {
        let letter = firstStr[i];
        for (let j = 1; j < strs.length; j++) {
            if (strs[j][i] !== letter) {
                letter = '';
                break;
            }
        }
        if (letter !== '') {
            prefix += letter;
        } else {
            break;
        }
    }
    return prefix;
};