551. Student Attendance Record I

You are given a string representing an attendance record for a student. The record only contains the following three characters:

1. 'A' : Absent. 
2. 'L' : Late.
3. 'P' : Present. 

A student could be rewarded if his attendance record doesn't contain more than one 'A' (absent) or more than two continuous 'L' (late). 

You need to return whether the student could be rewarded according to his attendance record.

Example 1:

Input: "PPALLP"Output: True

Example 2:

Input: "PPALLL"Output: False

根据题意，遇到2个以上的‘A’和连续的3个‘L’，返回false，否则返回true。代码如下：

public class Solution {    public boolean checkRecord(String s) {        int countL = 0, countA = 0;        for (char ch: s.toCharArray()) {            if (ch == 'L') {                countL ++;                if (countL >= 3) {                    return false;                }            } else if (ch == 'A') {                countA ++;                countL = 0;                if (countA >= 2) {                    return false;                }            } else {                countL = 0;            }        }        return true;    }}