import java.util.*;


public class Solution {
    /**
     * 代码中的类名、方法名、参数名已经指定,请勿修改,直接返回方法规定的值即可
     *
     *
     * @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 minLen = Integer.MAX_VALUE;

        for (String str : strs) {
            if (str.length() < minLen) {
                minLen = str.length();
            }
        }

        StringBuffer sb = new StringBuffer();
        oop:
        for (int i = 0; i < minLen; i++) {
            String str = strs[0].substring(i, i + 1);
            for (int j = 1; j < strs.length; j++) {
                String str1 = strs[j].substring(i, i + 1);
                if (!str.equals(str1)) {
                    break oop;
                }
            }
            sb.append(str);
        }
        return sb.toString();
    }
}