Watching shows without overlap

shows holds the schedules of live shows. [s, e] is a show that starts at minute s and ends at minute e. You can watch only one show at a time, and you watch each show you choose from start to finish. A show that starts at the moment another show ends can be watched right after it.

Complete the function solution, which returns the largest number of shows you can watch.

Function

solution(shows)

Constraints

• The length of shows is from 1 to 100,000.
• s and e are integers from 0 to 1,000,000,000, and s is less than e.
• Several shows may have the same start and end times.

Examples

Starter code

def solution(shows):
    answer = 0
    return answer