Problems

# Clocks

# Clocks

The driking-clock strikes so many beats every hour as face has them from **1** to **12**, and one time when the minute hand indicates **6** o’clock. Knowing the start and final period of **24**-hours period( which exposes in hours and minutes), count the general number of strikes for this term.

**Input**

Start and end timeof onecalendar dayin hours(**H**)and minutes(**M**)by a space (**0** ≤ **H** ≤ **23**, **0** ≤ **M** ≤ **59**).

**Output**

The answerto the problem.

Input example

13 30 15 10

Output example

7