# Clock

On Eeyore's birthday, he received a wristwatch with hands, and now he enjoys watching the hands move. He finds it fascinating to see how the minute hand catches up with the hour hand, overtakes it, and then continues to chase it.

One day, Kanga found Eeyore engrossed in this activity. She joined him and soon became curious about how many times Eeyore had seen the minute hand overtake the hour hand. To find out, she asked Eeyore when he started watching the clock, noted the start and current time, and then ran to Owl with the question. However, Owl was very busy and asked you to help.

As we know, the hour hand completes two full rotations in one day, while the minute hand completes 24.

## Input

The first line of the input file contains the time when Eeyore started watching the clock in the format HH:MM—the first two digits represent the hours, followed by a colon and two digits for the minutes.

The second line of the input file contains the end time in the same format.

It is known that Eeyore observed the clock for less than a day, but he could have started at midnight.

## Output

In the output file, print a single integer—the number of times the minute hand overtakes the hour hand during the observation period.

If such an event occurred exactly when Eeyore started or finished watching the clock, it should also be counted.