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 "";
        } else if (strs.length == 1) {
            return strs[0];
        }
        StringBuffer sb = new StringBuffer();
        char c;
        int strlen = strs[0].length();
        for (int i = 0; i < strlen; i++) {
            c = strs[0].charAt(i);
            for (int j = 1; j < strs.length; j++) {
            //如果超出字符串的长度或者与候选值不同,则直接返回
                if (i >= strs[j].length() || c != strs[j].charAt(i)) {
                    return sb.toString();
                }
            }
            sb.append(c);
        }
        return sb.toString();
    }
}