14. Longest Common Prefix (Easy)
https://leetcode.com/problems/longest-common-prefix/
Write a function to find the longest common prefix string amongst an array of strings.
If there is no common prefix, return an empty string "".
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:
All given inputs are in lowercase letters a-z.
Solutions
class Solution {
public String longestCommonPrefix(String[] strs) {
if (strs.length == 0) {
return "";
}
// take the first string as the pattern
String ans = strs[0];
for (int i = 1; i < strs.length; i++) {
String s = strs[i];
for (int j = 0; j < ans.length(); j++) {
if (j >= s.length() || ans.charAt(j) != s.charAt(j)) {
ans = ans.substring(0, j);
break;
}
}
}
return ans;
}
}