Build a Spreadsheet Grid | Dataford Interview Questions

Build a spreadsheet-like grid with cell editing and formula support, such as =SUM(A1,B1).

Asked in the Technical screen stage. Evaluate cell values with dependencies, using DFS as suggested by the author.

Implement evaluate_spreadsheet(edits). edits is a map from uppercase cell references to either an integer string or a formula in the form =SUM(arg1,arg2,...), where each argument is a cell reference or integer. A missing referenced cell has value 0. Return a map containing every edited cell and its evaluated integer value. Any cell involved in a dependency cycle, or depending on one, must have value "ERROR".

Examples: {"A1":"2","B1":"=SUM(A1,3)"} returns {"A1":2,"B1":5}. {"A1":"=SUM(B1)","B1":"=SUM(A1)"} returns {"A1":"ERROR","B1":"ERROR"}.

Constraints: At most 10,000 edited cells; formulas contain valid syntax and at most 20 arguments.

Constraints

At most 10,000 edited cells
Cell references use uppercase letters followed by a positive row number
Cell contents are integer strings or valid formulas of the form =SUM(arg1,arg2,...)
Each formula contains at most 20 arguments
A missing referenced cell has value 0

Function Signature

def evaluate_spreadsheet(edits):

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