Untitled

public class Calculator {
    public int add(int a, int b) {
        return a + b;
    }

    public int subtract(int a, int b) {
        return a - b;
    }

    public int multiply(int a, int b) {
        return a * b;
    }

    public int divide(int a, int b) {
        if (b == 0) {
            throw new IllegalArgumentException("Cannot divide by zero");
        }
        return a / b;
    }
}
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import org.junit.Test;
import static org.junit.Assert.*;

public class CalculatorTest {
    @Test
    public void testAdd() {
        Calculator calculator = new Calculator();
        int result = calculator.add(2, 3);
        assertEquals(5, result);
    }

    @Test
    public void testSubtract() {
        Calculator calculator = new Calculator();
        int result = calculator.subtract(5, 2);
        assertEquals(3, result);
    }

    @Test
    public void testMultiply() {
        Calculator calculator = new Calculator();
        int result = calculator.multiply(4, 3);
        assertEquals(12, result);
    }

    @Test
    public void testDivide() {
        Calculator calculator = new Calculator();
        int result = calculator.divide(10, 2);
        assertEquals(5, result);
    }

    @Test(expected = IllegalArgumentException.class)
    public void testDivideByZero() {
        Calculator calculator = new Calculator();
        calculator.divide(10, 0);
    }
}