You are given a?0-indexed?array of strings?details. Each element of?details?provides information about a given passenger compressed into a string of length?15. The system is such that:

• The first ten characters consist of the phone number of passengers.

• The next character denotes the gender of the person.

• The following two characters are used to indicate the age of the person.

• The last two characters determine the seat allotted to that person.

Return?the number of passengers who are?strictly?more than 60 years old.

?

Example 1:

Input: details = ["7868190130M7522","5303914400F9211","9273338290F4010"]

Output: 2

Explanation: The passengers at indices 0, 1, and 2 have ages 75, 92, and 40. Thus, there are 2 people who are over 60 years old.

Example 2:

Input: details = ["1313579440F2036","2921522980M5644"]

Output: 0

Explanation: None of the passengers are older than 60.

?

Constraints:

• 1 <= details.length <= 100

• details[i].length == 15

• details[i] consists of digits from '0' to '9'.

• details[i][10] is either 'M' or 'F' or 'O'.

• The phone numbers and seat numbers of the passengers are distinct.

easy題目，計算大于60的人數(shù)，根據(jù)題目計算一下即可；

Runtime:?0 ms, faster than?100.00%?of?Java?online submissions for?Number of Senior Citizens.

Memory Usage:?42.4 MB, less than?100.00%?of?Java?online submissions for?Number of Senior Citizens.