Code RoomRunning total of order value
MediumPrep Room Coding #5046

Running total of order value

CodingAlgorithms & data structuresMid–Senior~11 min

Given `orders` with columns `order_id`, `customer`, `amount`, `status` and `placed`, return a running total of `amount` in `placed` order as `running`. Return `order_id` and `running`, sorted by `placed` ascending.

Implement
running_total(orders: dataframe) → dataframe
Examples
in[{"__df__":[{"amount":120.5,"placed":"2024-01-05","status":"paid","customer":"ada","order_id":1},{"amount":80,"placed":"2024-01-07","status":"refunded","customer":"bo","order_id":2},{"amount":45.25,"placed":"2024-02-11","status":"paid","customer":"ada","order_id":3},{"amount":200,"placed":"2024-02-14","status":"paid","customer":"cy","order_id":4},{"amount":15.75,"placed":"2024-03-02","status":"pending","customer":"bo","order_id":5},{"amount":60,"placed":"2024-03-19","status":"paid","customer":"ada","order_id":6}]}]out[{"running":120.5,"order_id":1},{"running":200.5,"order_id":2},{"running":245.75,"order_id":3},{"running":445.75,"order_id":4},{"running":461.5,"order_id":5},{"running":521.5,"order_id":6}]
What a strong answer looks like

State your approach and its time/space complexity out loud before you optimize. Handle the edge cases (empty input, duplicates, overflow), and say why you chose this over the brute force. Green tests are the floor, not the grade.

0:00 of about 11 min
InputExpectedGot
[{"__df__":[{"amount":120.5,"placed":"2024-01-05","status":"paid","customer":"ada","order_id":1},{"amount":80,"placed":"2024-01-07","status":"refunded","customer":"bo","order_id":2},{"amount":45.25,"placed":"2024-02-11","status":"paid","customer":"ada","order_id":3},{"amount":200,"placed":"2024-02-14","status":"paid","customer":"cy","order_id":4},{"amount":15.75,"placed":"2024-03-02","status":"pending","customer":"bo","order_id":5},{"amount":60,"placed":"2024-03-19","status":"paid","customer":"ada","order_id":6}]}][{"running":120.5,"order_id":1},{"running":200.5,"order_id":2},{"running":245.75,"order_id":3},{"running":445.75,"order_id":4},{"running":461.5,"order_id":5},{"running":521.5,"order_id":6}]not run yetsample