Number of pairs in an array having sum equal to product | Java implementation of the approach ; Function to return the count of the required pairs ; Find the count of 0 s and 2 s in the array ; Find the count of required pairs ; Return the count ; Driver code
import java . util . * ; class GFG { static int sumEqualProduct ( int a [ ] , int n ) { int zero = 0 , two = 0 ; for ( int i = 0 ; i < n ; i ++ ) { if ( a [ i ] == 0 ) { zero ++ ; } if ( a [ i ] == 2 ) { two ++ ; } } int cnt = ( zero * ( zero - 1 ) ) / 2 + ( two * ( two - 1 ) ) / 2 ; return cnt ; } public static void main ( String [ ] args ) { int a [ ] = { 2 , 2 , 3 , 4 , 2 , 6 } ; int n = a . length ; System . out . print ( sumEqualProduct ( a , n ) ) ; } }