Soon the USU team will go to Vancouver to participate in the final of the ACM International Collegiate Programming Contest. They will be to take four different planes (three changes on the way)!
By the way, our team plans to return from Vancouver, so the two-way tickets are bought. The departure time (local time of the airport of departure) and the time of the arrival (local time of the destination airport) are printed on the tickets.
For example, the departure at 15.42 and the arrival at 16.23, and a return flight departs at 08.10 and arrives at 17.51.
Your task is to help to our team to find out how much does the time of the first airport differs from the one of the second. It is known that time in different airports differs by an integer amount of hours. The time of flights there and back may differ from each other not more than by 10 minutes.
The duration of a flight doesn't exceed 6 hours. The difference between airport local times is not greater than 5 hours.
There are two lines, each of them contains two numbers. The first line consists of the departure time and the arrival time of the flight there, the second one — the departure and the arrival times of the back flight. Numbers in the lines are separated with a space, an amount of minutes is separated from an amount of hours with a point.
Your program should write a non-negative integer (without extra zeroes) that corresponds to the difference in time between the two airports.
Problem Author: Magaz Asanov & Stanislav Vasilyev
Problem Source: Ural State Univerisity Personal Contest Online February'2001 Students Session