Find two prime numbers with given sum | Java program to find a prime number pair whose sum is equal to given number Java program to print super primes less than or equal to n . ; Generate all prime numbers less than n . ; Initialize all entries of boolean array as true . A value in isPrime [ i ] will finally be false if i is Not a prime , else true bool isPrime [ n + 1 ] ; ; If isPrime [ p ] is not changed , then it is a prime ; Update all multiples of p ; Prints a prime pair with given sum ; Generating primes using Sieve ; Traversing all numbers to find first pair ; Driver code
class GFG { static boolean SieveOfEratosthenes ( int n , boolean isPrime [ ] ) { isPrime [ 0 ] = isPrime [ 1 ] = false ; for ( int i = 2 ; i <= n ; i ++ ) isPrime [ i ] = true ; for ( int p = 2 ; p * p <= n ; p ++ ) { if ( isPrime [ p ] == true ) { for ( int i = p * p ; i <= n ; i += p ) isPrime [ i ] = false ; } } return false ; } static void findPrimePair ( int n ) { boolean isPrime [ ] = new boolean [ n + 1 ] ; SieveOfEratosthenes ( n , isPrime ) ; for ( int i = 0 ; i < n ; i ++ ) { if ( isPrime [ i ] && isPrime [ n - i ] ) { System . out . print ( i + " ▁ " + ( n - i ) ) ; return ; } } } public static void main ( String [ ] args ) { int n = 74 ; findPrimePair ( n ) ; } }