Build a Stateful Calculator
Build a Stateful Calculator UI Component
Implement a user interface (UI) component for a calculator.
Requirements
- Support digit input (0-9).
- Support the basic arithmetic operators: addition (
+), subtraction (-), multiplication (*), and division (/). - Implement an equals (
=) action to finalize the current calculation and display the total result. - Provide a reset action that clears all calculator state and resets the display.
- The display must update correctly and immediately during chained operations, not only after the final
=is pressed.
Example Behavior
Consider the input sequence: 1, +, 100, +, 20, =
- When the second
+operator is pressed, the display should immediately show the result of1 + 100, which is101. - After the
=operator is pressed, the display should show the final result of101 + 20, which is121.
Core Task
Explain in detail how you would model the internal state of the calculator and implement the logic for operator chaining to ensure the UI always reflects the correct current value.
AI interview prep
Core dilemma
The central engineering conflict is designing a robust state management system that correctly interprets a sequence of user inputs as an arithmetic expression, handles intermediate calculations for immediate UI updates, and manages operator chaining while potentially addressing operator precedence and numerical precision.
3 tradeoffs and 3 stress tests locked
Interview prep
Unlock the interviewer X-Ray rubric, tradeoff matrix, stress tests, clarifying questions, and key concepts.
Build a Stateful Calculator
Build a Stateful Calculator UI Component
Implement a user interface (UI) component for a calculator.
Requirements
- Support digit input (0-9).
- Support the basic arithmetic operators: addition (
+), subtraction (-), multiplication (*), and division (/). - Implement an equals (
=) action to finalize the current calculation and display the total result. - Provide a reset action that clears all calculator state and resets the display.
- The display must update correctly and immediately during chained operations, not only after the final
=is pressed.
Example Behavior
Consider the input sequence: 1, +, 100, +, 20, =
- When the second
+operator is pressed, the display should immediately show the result of1 + 100, which is101. - After the
=operator is pressed, the display should show the final result of101 + 20, which is121.
Core Task
Explain in detail how you would model the internal state of the calculator and implement the logic for operator chaining to ensure the UI always reflects the correct current value.