﻿ Java - Multiply two integers without multiply operator

# Java: Multiply two specified integers without using the multiply operator

## Java Basic: Exercise-168 with Solution

Write a Java program to multiply two given integers without using the multiply operator (*).

Sample Solution:

Java Code:

``````// Importing the required Java utilities package
import java.util.*;

// Defining a class named Solution
public class Solution {

// Method to multiply two integers without using the multiplication operator
public static int multiply(int n1, int n2) {
int result = 0; // Initializing the variable to store the result of multiplication
boolean negative_num = (n1 < 0 && n2 >= 0) || (n2 < 0 && n1 >= 0); // Checking if the result will be negative
boolean positive_num = !negative_num; // Determining if the result will be positive

n1 = Math.abs(n1); // Converting n1 to its absolute value to simplify multiplication

// Loop to perform multiplication without using the * operator
for (int i = 0; i < n1; i++) {
// Handling the addition or subtraction based on the signs of the numbers
if (negative_num && n2 > 0 || positive_num && n2 < 0)
result -= n2; // Subtracting n2 from the result
else
result += n2; // Adding n2 to the result
}

return result; // Returning the final result of multiplication
}

// The main method of the program
public static void main(String[] args) {
Scanner in = new Scanner(System.in); // Creating a Scanner object to read input from the user

// Asking the user to input the first number
System.out.print("Input the first number: ");
int n1 = in.nextInt(); // Reading the first integer input from the user

// Asking the user to input the second number
System.out.print("Input the second number: ");
int n2 = in.nextInt(); // Reading the second integer input from the user

// Displaying the result of the multiplication by calling the multiply method
System.out.println("\nResult: " + multiply(n1, n2));
}
}
```
```

Sample Output:

```Input the first number:  25
Input the second number:  5

Result: 125
```

Flowchart: Java Code Editor: