Twin Prime Numbers in C, C++, Java & Python – Code with Explanation & Examples in Short and Simple

   

C Program

#include <stdio.h>

int isPrime(int n) {
    if (n < 2) return 0;
    for (int i = 2; i * i <= n; i++)
        if (n % i == 0) return 0;
    return 1;
}

int main() {
    int a, b;
    scanf("%d %d", &a, &b);
    if (isPrime(a) && isPrime(b) && (b - a == 2))
        printf("%d and %d are Twin Primes", a, b);
    else
        printf("%d and %d are Not Twin Primes", a, b);
}

C Output

Input:
11 13
Output:
11 and 13 are Twin Primes

C++ Program

#include <iostream>
using namespace std;

bool isPrime(int n) {
    if (n < 2) return false;
    for (int i = 2; i * i <= n; i++)
        if (n % i == 0) return false;
    return true;
}

int main() {
    int a, b;
    cin >> a >> b;
    if (isPrime(a) && isPrime(b) && (abs(a - b) == 2))
        cout << a << " and " << b << " are Twin Primes";
    else
        cout << a << " and " << b << " are Not Twin Primes";
}

C++ Output

Input:
17 19
Output:
17 and 19 are Twin Primes

JAVA Program

import java.util.Scanner;

public class TwinPrime {
    static boolean isPrime(int n) {
        if (n < 2) return false;
        for (int i = 2; i * i <= n; i++)
            if (n % i == 0) return false;
        return true;
    }

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int a = sc.nextInt(), b = sc.nextInt();
        if (isPrime(a) && isPrime(b) && Math.abs(a - b) == 2)
            System.out.println(a + " and " + b + " are Twin Primes");
        else
            System.out.println(a + " and " + b + " are Not Twin Primes");
    }
}

JAVA Output

Input:
29 31
Output:
29 and 31 are Twin Primes

Python Program

def is_prime(n):
    if n < 2: return False
    for i in range(2, int(n**0.5)+1):
        if n % i == 0: return False
    return True

a, b = map(int, input().split())
if is_prime(a) and is_prime(b) and abs(a-b) == 2:
    print(a, "and", b, "are Twin Primes")
else:
    print(a, "and", b, "are Not Twin Primes")

Python Output

Input:
41 43
Output:
41 and 43 are Twin Primes

In-Depth Explanation

Example

Twin primes are prime number pairs with a difference of 2. For instance, (11, 13), (17, 19), (29, 31), and (41, 43) are twin primes. The two numbers must be prime, and the difference must be 2. If either of the conditions is not met, the pair does not qualify as twin primes.

Real-Life Analogy

Imagine two inseparable best friends always seen together but having only a slight space between them, like two individuals standing two steps behind each other in a queue. They are near enough to be referred to as "twin primes." In the same manner, twin primes are siblings of prime numbers, always coming very close to one another with only an extremely small difference of 2.

Why It Matters

Twin primes are important in number theory as they relate directly to one of the most well-known unsolved mathematics problems: the Twin Prime Conjecture. The conjecture postulates that twin primes are infinite in number, although this hasn't been proven yet. Despite the fact that we continue to discover increasingly more and more twin primes as numbers increase, no one has yet established whether or not they will go on forever. This maintains mathematicians and computer scientists interested, and algorithms for discovering large twin primes remain an active research area.

Learning Insight

From a coding point of view, verification of twin primes makes you learn about prime number verification algorithms, how to optimize loops, and applying logical conditions in combination. Prime numbers are usually learned by beginners first, but twin primes push the logic further, demonstrating how mathematical principles can be stacked and put together to create new problems.

Use in Interviews and Projects

Interviewers are fond of questioning primes and twin primes since they intertwine mathematical logic with effective coding. The interviewer may ask you to implement a prime check function, and then expand it to twin primes, to check how you modularize code and how you reuse functions. Prime numbers have a very significant part in cryptography, and although twin primes are not used directly to encrypt, they assist in constructing mathematical understanding of the way primes group and spread.

SEO-Optimized Conclusion

Twin primes are a fascinating area of mathematics and computer science, particularly for candidates gearing up for coding interviews and competitive programming. Knowing how to test for prime numbers and then generalizing the logic to discover twin primes enhances problem-solving ability. Twin primes are practiced in programming as problems to reinforce ideas of loops, conditionals, and algorithms for testing primes. Practice twin prime number programs, if you are learning C, C++, Java, or Python. This will make you feel confident about mathematical logic and effective coding techniques as you prepare for exams or interviews.