题解 | #最长公共前缀#

import java.util.*;


public class Solution {
    /**
     * 
     * @param strs string字符串一维数组 
     * @return string字符串
     */
    public String longestCommonPrefix (String[] strs) {
        if(strs.length == 0){
            return "";
        }
        if(strs.length == 1){
            return strs[0];
        }
        int min = strs[0].length();
        for(int i = 1; i < strs.length; i++){
            min = Math.min(min, strs[i].length());
            min = subStr(strs[i-1], strs[i],min);
        }
        if(min == 0) return "";
        return strs[0].substring(0,min);
    }
    
    public int subStr(String str1, String str2, int n){
        for(int i = 1; i <= n; i++){
            if(str1.charAt(i-1) != str2.charAt(i-1)){
                return i-1;
            }
        }
        return n;
    }
}