Question

Write a java program to print prime Fibonacci terms upto n terms. Input n as the limit of the series.​

Answer 1

Answer:

// Java program to print prime numbers

// present in Fibonacci series.

class PrimeAndFib

{

// Function to check perfect square

Boolean isSquare(int n)

{

int sr = (int)Math.sqrt(n);

return (sr * sr == n);

}

// Prints all numbers less than or equal

// to n that are both Prime and Fibonacci.

static void printPrimeAndFib(int n)

{

// Using Sieve to generate all

// primes less than or equal to n.

Boolean[] prime = new Boolean[n + 1];

// memset(prime, true, sizeof(prime));

for (int p = 0; p <= n; p++)

prime[p] = true;

for (int p = 2; p * p <= n; p++) {

// If prime[p] is not changed,

// then it is a prime

if (prime[p] == true) {

// Update all multiples of p

for (int i = p * 2; i <= n; i += p)

prime[i] = false;

}

}

// Now traverse through the range and

// print numbers that are both prime

// and Fibonacci.

for (int i=2; i<=n; i++) {

double sqrt = Math.sqrt(5 * i * i + 4);

double sqrt1 = Math.sqrt(5 * i * i - 4);

int x = (int) sqrt;

int y = (int) sqrt1;

if (prime[i]==true && (Math.pow(sqrt,2) ==

Math.pow(x,2) || Math.pow(sqrt1,2) ==

Math.pow(y,2)))

System.out.print(i+" ");

}

}

// driver program

public static void main(String s[])

{

int n = 30;

printPrimeAndFib(n);

}

}