1854 Maximum Population Year

You are given a 2D integer array logs where each logs[i] = [birthi, deathi] indicates the birth and death years of the ith person.

The population of some year x is the number of people alive during that year. The ith person is counted in year x's population if x is in the inclusive range [birthi, deathi - 1]. Note that the person is not counted in the year that they die.

Return the earliest year with the maximum population.

Example 1:

Input: logs = [[1993,1999],[2000,2010]]
Output: 1993
Explanation: The maximum population is 1, and 1993 is the earliest year
with this population.

Example 2:

Input: logs = [[1950,1961],[1960,1971],[1970,1981]]
Output: 1960
Explanation: 
The maximum population is 2, and it had happened in years 1960 and 1970.
The earlier year between them is 1960.

Constraints:

  • 1 <= logs.length <= 100
  • 1950 <= birthi < deathi <= 2050
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class Solution:
    def maximumPopulation(self, logs: List[List[int]]) -> int:
        events = []
        for birth_year, death_year in logs:
            events.append((birth_year, 1))
            events.append((death_year, -1))
        
        events.sort()
        current_pop = 0
        max_pop = 0
        max_pop_year = -1
        for year, delta in events:
            current_pop += delta
            if current_pop > max_pop:
                max_pop = current_pop
                max_pop_year = year
        return max_pop_year