##### Canadian Computing Competition: 2016 Stage 1, Junior #4

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`

, in which `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.

## Comments

are the times fully inclusive? eg if she leaves at 6:40, is she on the road at 6:40? or does that only start at 6:41? i have the same question regarding the rush hour traffic times, I will assume for now that everythings inclusive

Is rush hour traffic inclusive or exclusive?

exclusive I'm pretty sure

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