题目

Write a function to find the longest common prefix string amongst an array of strings.

思路

首先找出数组的String最小长度，避免index越界。之后从i=0开始遍历所有数组中的String的i位，检查是否相等，若相等则最大前缀+1，若不相等则退出循环，返回最大前缀

代码

public class Solution { public String longestCommonPrefix(String[] strs) { int i = 0; String lcp = ""; if(strs.length == 0) return lcp; int minLength = strs[0].length(); for(int j = 0 ; j < strs.length ; ++ j){ if(strs[j].length() < minLength) minLength = strs[j].length(); } while(i < minLength){ char c = strs[0].charAt(i); int flag = 1; for(int j = 0 ; j < strs.length ; ++ j){ if(strs[j].charAt(i) != c){ flag = 0 ; break; } } if(flag == 0) break; if(flag == 1){ lcp = lcp + c; ++i; } } return lcp; } }