#938. Fewest platforms
You get the arrival and departure time [a, d] of each train (both included). Find the largest number of trains that are at the station at the same time.
### Input
n, then n lines `a d`.
### Output
A number.
Examples
Input
1 9 15
Output
1
Input
6 1 7 11 15 12 13 0 5 10 14 7 11
Output
3
💡 You can solve it with Python, JavaScript or blocks. Read the input line by line with input(). Don't print a question (like input("Number: ")). Print exactly what the output asks for, nothing more.