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)

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

此題較為簡單，在於驗證字串中是否包含特定字元，Accepted程式碼如下：

class Solution {
    public boolean checkRecord(String s) {
        int aNum = 0;
        for (int i = 0; i < s.length(); i++) {
            if (s.charAt(i) == 'A') {
                aNum++;
            }
        }
        if (aNum > 1) {
            return false;
        }
        if (s.contains("LLL")) {
            return false;
        }
        return true;
    }
}