Introduction

Prime factorization is a mathematical process where a number is expressed as a product of its prime factors.
This program demonstrates how to find the prime factors of a given number using Go, showcasing loops, conditionals, and number theory in action.

Objective

The objective of this project is to create a program that calculates and displays the prime factors of a user-provided number.
This helps learners understand number theory and how to implement mathematical concepts in Go programming.

Code

package main

import (
	"fmt"
)

// Function to find and return the prime factors of a number
func primeFactors(n int) []int {
	factors := []int{}
	// Divide n by 2 until it is odd
	for n%2 == 0 {
		factors = append(factors, 2)
		n /= 2
	}

	// Check for odd factors from 3 onwards
	for i := 3; i*i <= n; i += 2 { for n%i == 0 { factors = append(factors, i) n /= i } } // If n is still greater than 2, it must be prime if n > 2 {
		factors = append(factors, n)
	}

	return factors
}

func main() {
	var num int
	fmt.Println("Welcome to the Prime Factorization Program!")
	fmt.Print("Enter a number to find its prime factors: ")
	fmt.Scanln(&num)

	if num <= 1 {
		fmt.Println("Please enter a number greater than 1.")
		return
	}

	factors := primeFactors(num)
	fmt.Printf("The prime factors of %d are: %v\n", num, factors)
}

Explanation

The program structure is as follows:

• Prime Factorization Function: The primeFactors function calculates the prime factors by:
  • Dividing the number by 2 repeatedly to account for all factors of 2.
  • Iterating through odd numbers from 3 onwards to find other factors.
  • Appending the remaining number if it is greater than 2, as it is prime.
• Main Function: The main function takes user input for the number, validates it, and calls the prime factorization function.
  The result is displayed to the user.

How to Run the Program

1. Ensure you have Go installed on your system. You can download it from
   Go’s official website.
2. Save the code in a file named prime_factorization.go.
3. Open a terminal and navigate to the directory containing the file.
4. Run the program with the following command:

   go run prime_factorization.go

5. Enter a number greater than 1 when prompted to find its prime factors.