Design a Driver Payroll System

Problem Statement

Design an in-memory payroll tracking system for a ride-sharing company. The system tracks earnings generated by drivers over time and allows querying individual driver earnings as well as total company payroll across specified time windows.

Implement the DriverPayroll class:

• __init__(): Initializes the payroll system.
• record_earning(driver_id: str, timestamp: int, amount: int) -> None: Records an earning amount (in cents) for driver_id at a given timestamp. Calls to record_earning are guaranteed to arrive in non-decreasing order of timestamp globally.
• get_driver_earnings(driver_id: str, start_time: int, end_time: int) -> int: Returns the total earnings for driver_id between start_time and end_time, inclusive. If the driver has no earnings in this range or does not exist, return 0.
• get_total_payroll(start_time: int, end_time: int) -> int: Returns the sum of earnings across all drivers between start_time and end_time, inclusive.

Example

payroll = DriverPayroll()
payroll.record_earning("driver_1", 10, 500)   # $5.00 for driver_1 at t=10
payroll.record_earning("driver_2", 15, 750)   # $7.50 for driver_2 at t=15
payroll.record_earning("driver_1", 20, 300)   # $3.00 for driver_1 at t=20
payroll.record_earning("driver_1", 25, 200)   # $2.00 for driver_1 at t=25

# Driver 1 earnings between t=10 and t=20 (500 + 300)
assert payroll.get_driver_earnings("driver_1", 10, 20) == 800

# Total payroll between t=12 and t=22 (750 + 300)
assert payroll.get_total_payroll(12, 22) == 1050

# Query with no earnings
assert payroll.get_driver_earnings("driver_2", 16, 30) == 0
assert payroll.get_driver_earnings("driver_3", 0, 100) == 0

Constraints

• 1 <= len(driver_id) <= 32
• 1 <= timestamp <= 10^9
• 1 <= amount <= 10^6
• 0 <= start_time <= end_time <= 10^9
• At most 2 * 10^5 total calls across all methods.
• Multiple earnings may be recorded at the exact same timestamp (for the same or different drivers).

Edge Cases to Consider

• Querying a driver_id that was never recorded.
• Time windows that cover no events or encompass all recorded events.
• Multiple earnings occurring at the exact same start_time or end_time.