Multi-Level Banking System

Implement a simplified banking system that processes operations in timestamp order. The system has four levels, and every later level must preserve all earlier functionality. Timestamps are strictly increasing non-negative integers. Before processing each operation, execute every scheduled payment whose execution time is no later than that operation's timestamp. Input format The first line contains Q, the number of operations. Each following line is one operation. Level 1: Accounts, deposits, and transfers CREATE timestamp accountId Create an account. Print false if accountId is already active; otherwise create it with balance 0 and print true. DEPOSIT timestamp accountId amount Deposit positive integer amount into an active account. Print the new balance, or null if the account does not exist. TRANSFER timestamp fromId toId amount Transfer positive integer amount from fromId to toId. Both accounts must be active, distinct, and the sender must have sufficient funds. On success, update balances, add amount to the sender's total outgoing amount, and print the sender's new balance. Otherwise print null. Level 2: Spending leaderboard TOP timestamp n Print up to n currently active accounts with the largest total outgoing amount. Outgoing amount includes successful transfer amounts sent by the account and successful scheduled payments, but not deposits. Sort by outgoing amount descending, then by accountId lexicographically ascending. Format: id1(total1), id2(total2), .... Print an empty line if no active account exists. Level 3: Scheduled payments SCHEDULE timestamp accountId amount delay Create a scheduled debit for accountId, to execute at timestamp + delay. If the account does not exist, print null. Otherwise assign globally increasing IDs payment1, payment2, ... and print the new ID. Payments due at the same time execute in creation order. At execution time, debit the account and increase its outgoing total if it is still active and has enough balance. Otherwise, the payment fails and is discarded. CANCEL timestamp accountId paymentId Cancel a payment only if it has not executed or been canceled and is currently owned by accountId. Print true on success and false otherwise. Level 4: Account merging and historical balance MERGE timestamp targetId sourceId Merge sourceId into targetId; both must be distinct active accounts. On success, move the source balance into the target, add source outgoing total to target outgoing total, reassign all pending source payments to the target, deactivate the source, and print the target's resulting balance. Print null if either account is inactive/nonexistent or the IDs are equal. QUERY timestamp accountId queryTime Return the balance of accountId at queryTime, after all operations processed at that time. Print null if the account did not exist at queryTime, or had already been merged and deactivated before that time; otherwise print its balance at that time. Print one result for every input operation. amount <= 10^9 and Q <= 2 * 10^5. Example Input 8 CREATE 1 alice CREATE 2 bob DEPOSIT 3 alice 100 TRANSFER 4 alice bob 30 TOP 5 2 SCHEDULE 6 bob 50 2 QUERY 7 bob 50 TOP 8 2 Output true true 100 70 alice(30), bob(0) payment1 130 bob(50), alice(30) Example Input 8 CREATE 1 alice CREATE 2 bob DEPOSIT 3 alice 100 TRANSFER 4 alice bob 30 TOP 5 2 SCHEDULE 6 bob 50 2 QUERY 7 bob 50 TOP 8 2 Output true true 100 70 alice(30), bob(0) payment1 130 bob(50), alice(30)