Calculator Exercise

Prerequisites

• .NET 8 SDK

Build

From the repository root:

dotnet build calculator_exercise/calculator_exercise.csproj

Run

Pass an instruction-file path after --:

dotnet run --project calculator_exercise/calculator_exercise.csproj -- path/to/instructions.txt

Assumptions

• Input is supplied in a .txt file, with one operator and one number on each non-empty line.
• Numbers are parsed as decimal values using . as the decimal separator.
• Operators are case-insensitive.
• Blank lines and repeated whitespace are ignored.
• apply must appear exactly once and only as the final instruction.
• Invalid input, missing files, and division by zero produce a clear error message and a non-zero exit code.