Leetcode- student attendance record i- simple

title ：551 Student attendance records I- Simple

subject

Give you a string s Indicates a student's attendance record , Each character is used to mark the attendance of the day （ Absence from duty 、 late 、 Be present ）. The record contains only the following three characters ：

‘A’：Absent, Absence from duty
‘L’：Late, late
‘P’：Present, Be present
If students can meanwhile The following two conditions are satisfied , You can get attendance reward ：

Press Total attendance meter , Student absenteeism （‘A’） Strictly Less than two days .
Student Can't There is continuity 3 Heaven or continuity 3 More than days late （‘L’） Record .
If students can get attendance rewards , return true ; otherwise , return false .

Example 1

 Input ：s = "PPALLP"
 Output ：true
 explain ： Students are absent less than  2  Time , And it does not exist.  3  Continuous lateness record of days or more .

Example 2

 Input ：s = "PPALLL"
 Output ：false
 explain ： The students were late for the last three days in a row , Therefore, the conditions for attendance reward are not met .

Tips

• 1 <= s.length <= 1000
• s[i] by 'A'、'L' or 'P'

Code Java

		public boolean checkRecord(String s) {
    
        StringBuilder sb = new StringBuilder(s);
        int countA = 0; //  Record absence days , if countA >= 2  return false
        int countL = 0; //  Record late days , if countL == 3  return false
        for (int i = 0; i < sb.length(); i++) {
    
            if (sb.charAt(i) == 'A') {
    
                countA ++;
                countL = 0;
                if (countA >= 2) return false;
            } else if (sb.charAt(i) == 'L') {
    
                countL ++;
                if (countL == 3) return false;
            } else countL = 0;
        }
        return true;
    }