from bisect import bisect_left
from structures import run_operations

class Calendar:
    def __init__(self):
        self.bookings = []

    def book(self, start, end):
        i = bisect_left(self.bookings, (start, end))
        if i and self.bookings[i - 1][1] > start:
            return False
        if i < len(self.bookings) and self.bookings[i][0] < end:
            return False
        self.bookings.insert(i, (start, end))
        return True