This project was developed as part of a challenge to implement a calculator in "exam mode." This means it was coded without any external help or internet access, relying purely on knowledge and problem-solving skills.
The calculator processes mathematical expressions by first tokenizing the input string. Each character is identified as part of a number or an operator, and operators are assigned priorities to ensure correct order of operations.
Given the equation:
2 + 2 * 3
It is tokenized as:
(N) [2]
(O) [+] - (priority: 1)
(N) [2]
(O) [*] - (priority: 2)
(N) [3]
Here, multiplication * has a higher priority than addition +, ensuring the correct calculation order.
Brackets () modify the priority of operators, enforcing a different order of evaluation.
Example:
(2 + 2) * 3
Tokenized as:
(N) [2]
(O) [+] - (priority: 4)
(N) [2]
(O) [*] - (priority: 2)
(N) [3]
Since the addition is inside parentheses, its priority is increased, ensuring it is evaluated before multiplication.
The calculator currently supports the following operators:
+(Addition)-(Subtraction)*(Multiplication)/(Division)^(Exponentiation)
The tokenizer correctly identifies negative numbers, even in complex expressions with multiple negative signs.
Example:
-1 + -2 * ------3 / ---4
Tokenized as:
(N) [-1]
(O) [+] - (priority: 1)
(N) [-2]
(O) [*] - (priority: 2)
(N) [3]
(O) [/] - (priority: 2)
(N) [-4]
This ensures proper evaluation of negative numbers and consecutive negative signs.
- Expressions are tokenized and operators are assigned priorities.
- Brackets increase operator priority for correct evaluation.
- Supports basic arithmetic operations and exponentiation.
- Properly handles negative numbers and chained negative signs.