// Package calculator does simple calculations.
package calculator // Add takes two numbers and returns the result of adding them together.

import (
	"errors"
)

func Add(a, b int) int {
	return a + b
}

func Subtract(a, b int) int {
	return a - b
}

func Multiply(a, b int) int {
	return a * b
}

func Divide(a, b int) (int, error) {
    if b == 0 {
        return 0, errors.New("division by zero not allowed")
    }
    return a / b, nil
}