feat(accounts-transactions): add accounts transactions challenge

Author: jordanpaulchan

accounts-transactions/accounts-transactions.py

@@ -0,0 +1,59 @@
+from bisect import bisect_right
+
+
+class Account():
+ def __init__(self, account_id, ts, value):
+ self.account_id = account_id
+ self.timestamps = [ts]
+ self.balances = [value]
+ self.values = [value]
+
+
+class Accounts:
+ def __init__(self):
+ self.accounts = {}
+
+ def credit(self, account_id, ts, value):
+ if account_id not in self.accounts:
+ self.accounts.setdefault(
+ account_id, Account(account_id, ts, value))
+ else:
+ account = self.accounts[account_id]
+ account.timestamps.append(ts)
+ account.balances.append(account.balances[-1] + value)
+ account.values.append(value)
+
+ def debit(self, account_id, ts, value):
+ if account_id not in self.accounts:
+ self.accounts.setdefault(
+ account_id, Account(account_id, ts, -value))
+ else:
+ account = self.accounts[account_id]
+ account.timestamps.append(ts)
+ account.balances.append(account.balances[-1] - value)
+ account.values.append(-value)
+
+ def current(self, account_id):
+ if account_id not in self.accounts:
+ return None
+ account = self.accounts[account_id]
+ return account.balances[-1]
+
+ def balance_change(self, account_id, start_ts, end_ts):
+ if account_id not in self.accounts:
+ return None
+ account = self.accounts[account_id]
+ start_idx = bisect_right(account.timestamps, start_ts)
+ end_idx = bisect_right(account.timestamps, end_ts)
+
+ return account.balances[end_idx - 1] - account.balances[start_idx - 1]
+
+
+accounts = Accounts()
+accounts.credit(1, 1, 100)
+accounts.debit(1, 3, 50)
+accounts.credit(1, 5, 20)
+accounts.debit(1, 7, 10)
+print(accounts.current(1))
+print(accounts.balance_change(1, 2, 6))
+print(accounts.balance_change(1, 3, 5))