551. Student Attendance Record I

Posted 2021-02-12 ruruozhenhao

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

 

Approach #1: Brut force. [C++]

class Solution {
public:
    bool checkRecord(string s) {
        int numOfA = 0, numOfL = 0;
        for (int i = 0; i < s.length(); ++i) {
            if (s[i] == ‘A‘) numOfA++;
            if (s[i] == ‘L‘) numOfL++;
            else numOfL = 0;
            if (numOfA > 1 || numOfL > 2) return false; 
        }

        return true;
    }
};