Maximum Profit from Stock Prices by Date and Ticker

Problem: Calculate Maximum Profit from Stock Prices by Date and Ticker You are given a list of stock price records. Each record contains: date: a date string in YYYY-MM-DD format ticker: a stock name/symbol without spaces price: the stock price on that date, represented as a non-negative integer You may complete at most one transaction: Choose one stock; Buy it on one date; Sell it on a later date; The buy and sell must be for the same stock; The sell date must be strictly later than the buy date. Return the maximum possible profit across all stocks. If no positive profit is possible, return 0. The input records may not be sorted by date, so you must handle chronological ordering correctly. Input Format n date_1 ticker_1 price_1 date_2 ticker_2 price_2 ... date_n ticker_n price_n Constraints: 1 <= n <= 200000 date_i is a valid date string in YYYY-MM-DD format ticker_i contains only letters, digits, and underscores, and has length at most 20 0 <= price_i <= 10^9 Output Format Print one integer: the maximum profit. Example 1 6 2024-01-03 AAPL 10 2024-01-01 AAPL 5 2024-01-02 AAPL 8 2024-01-01 MSFT 20 2024-01-04 MSFT 25 2024-01-03 MSFT 18 Output: 7 Explanation: Buy MSFT at 18 and sell later at 25, giving profit 7. Example 2 4 2024-01-01 AAPL 10 2024-01-02 AAPL 7 2024-01-03 AAPL 5 2024-01-04 AAPL 3 Output: 0 Example Input 6 2024-01-03 AAPL 10 2024-01-01 AAPL 5 2024-01-02 AAPL 8 2024-01-01 MSFT 20 2024-01-04 MSFT 25 2024-01-03 MSFT 18 Output 7