【Leetcode】14. Longest Common Prefix

Question:

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

LeetCode submission:

public class Solution {
public String longestCommonPrefix(String[] strs) {
String ans = "";
if (strs.length == 0 || strs == null) {
return "";
}
if(strs.length==1) ans=strs[0];

String min = strs[0];

for (int i = 1; i < strs.length; i++) {// strs数组中字符串的个数
//System.out.println(strs.length);

while (strs[i].indexOf(min) != 0) {
min = min.substring(0, min.length() - 1);
}
ans=min;
}
System.out.println(ans);
return ans;
}
}

Executable code：

public class L14 {

public String longestCommonPrefix(String[] strs) {
String ans = "";
if (strs.length == 0 || strs == null) {
return "";
}
if(strs.length==1) ans=strs[0];

String min = strs[0];

for (int i = 1; i < strs.length; i++) {// strs数组中字符串的个数
//System.out.println(strs.length);

while (strs[i].indexOf(min) != 0) { //当strs[]与min无法匹配时将min字符串长度减一
min = min.substring(0, min.length() - 1);
}
ans=min;
}
System.out.println(ans);
return ans;
}

public static void main(String[] args) {
L14 l14 = new L14();
String[] strs = {"a","a","b"};
l14.longestCommonPrefix(strs);
}
}

Note：

strs[i].indexOf(min)//返回min的第一个字符在strs[i]中的第一个位置，

min = min.substring(0, min.length() - 1);////当strs[]与min无法匹配时将min字符串长度减一