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 ""。

示例 1:

输入: ["flower","flow","flight"]
输出: "fl"

示例 2:

输入: ["dog","racecar","car"]
输出: ""
解释: 输入不存在公共前缀。

就是水平扫描

import java.util.*;
class Solution {
	public static void main(String[] args) {
		String[] strings = new String[] {"flag","flow","flower"};
		Solution solution = new Solution();
		System.out.println(solution.longestCommonPrefix(strings)+"~");
	}
    public String longestCommonPrefix(String[] strs) {
      if(strs.length<=0) return "";
      if(strs.length==1) return strs[0];
      String sameString = Solution.thesame(strs[0], strs[1]);
      for(String each:strs) {
    		sameString = Solution.thesame(sameString, each);
      }
      return sameString;
    }
    public static String thesame(String str1,String str2) {
    	String sameString = "";
    	for(int i=0;i<str1.length()&&i<str2.length();++i) {
    		if(str1.charAt(i)==str2.charAt(i)) {
    			sameString+=str1.charAt(i);
    		}
    		
    	}
    	
    	return sameString;
    	
    	
    }
}