English
14. Longest Common Prefix 
 
Problem Statement
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: strs = ["flower","flow","flight"] Output: "fl"
Example 2:
Input: strs = ["dog","racecar","car"] Output: "" Explanation: There is no common prefix among the input strings.
Constraints:
1 <= strs.length <= 2000 <= strs[i].length <= 200strs[i]consists of only lowercase English letters.
Solution:
java
class Solution {
  public String longestCommonPrefix(String[] strs) {
    String res = strs[0];
    for (int i = 1; i < strs.length; i++)
      while (!strs[i].startsWith(res))
        res = res.substring(0, res.length() - 1);
    return res;
  }
}
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