ICS 4U – PROGRAM 04
TIME OF ARRIVAL

Problem Description

Fiona commutes to work each day. If there is no rush-hour traffic, her commute time is 2 hours. However, there is often rush-hour traffic.

Specifically, rush-hour traffic occurs from 07:00 (7am) until 10:00 (10am) in the morning and 15:00 (3pm) until 19:00 (7pm) in the afternoon. During rush-hour traffic, her speed is reduced by half. She leaves either on the hour (at XX:00), 20 minutes past the hour (at XX:20), or 40 minutes past the hour (at XX:40).

Given Fiona’s departure time, at what time does she arrive at work?

Input Specification

The input will be one line, which contains an expression of the form HH:MM, where HH is one of the 24 starting hours (00, 01, . . ., 23) and MM is one of the three possible departure minute times (00, 20, 40).

Output Specification

Output the time of Fiona’s arrival, in the form HH:MM.

Sample Input 1

05:00

Output for Sample Input 1

07:00

Explanation for Output for Sample Input 1

Fiona does not encounter any rush-hour traffic, and leaving at 5am, she arrives at exactly 7am.

Sample Input 2

07:00

Output for Sample Input 2

10:30

Explanation for Output for Sample Input 2

Fiona drives for 3 hours in rush-hour traffic, but only travels as far as she normally would after driving for 1.5 hours. During the final 30 minutes (0.5 hours) she is driving in non-rush-hour traffic.

Sample Input 3

23:20

Output for Sample Input 3

01:20

Explanation for Output for Sample Input 3

Fiona leaves at 11:20pm, and with non-rush-hour traffic, it takes two hours to travel, so she arrives at 1:20am the next day.

SMALL HINT

You will have read the input as a string and then convert parts of it into an integer.

Converting a string into an integer can easily be done. Here is an example:

String str = "12345";

int num = Integer.parseInt(str);

Of course, the string str must contain only numbers.