【一次过】Lintcode 1178. Student Attendance Record I

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

• 'A' : Absent.
• 'L' : Late.
• '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.

样例

Example 1:

Input: "PPALLP"
Output: True

Example 2:

Input: "PPALLL"
Output: False

输入测试数据 (每行一个参数)

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解题思路1：

直接遍历即可。

public class Solution {
    /**
     * @param s: a string
     * @return: whether the student could be rewarded according to his attendance record
     */
    public boolean checkRecord(String s) {
        // Write your code here
        int cntA = 0, cntL = 0;
        char[] ss = s.toCharArray();
        
        for(char c : ss){
            if(c == 'A'){
                ++cntA;
                cntL = 0;
            }else if(c == 'L')
                ++cntL;
            else
                cntL = 0;
            
            if(cntA>1 || cntL>2)
                return false;
        }
        
        return true;
    }
}

解题思路2：

使用字符串匹配函数。

public class Solution {
    /**
     * @param s: a string
     * @return: whether the student could be rewarded according to his attendance record
     */
    public boolean checkRecord(String s) {
        // Write your code here
        return s.indexOf('A') == s.lastIndexOf('A') && !s.contains("LLL");
    }
}