Function to calculate sum of all the GCD pairs
sumOfGcdPairs ( ) ; int N = 4 ; cout << " Summation ▁ of ▁ " << N << " ▁ = ▁ " << result [ N ] << endl ; ; N = 12 ; cout << " Summation ▁ of ▁ " << N << " ▁ = ▁ " << result [ N ] << endl ; N = 5000 ; cout << " Summation ▁ of ▁ " << N << " ▁ = ▁ " << result [ N ] ; return 0 ; }