Question

What is the output of the program?

int function1( int x, int& y) {

if( x % 2 == 0) {

x = x + y;

   }

      y = y - x;

      return x;

}

int main() {

      int a, b, result;

cin >> a >> b;

result = function1(a, b);

cout << "a = "<< a << ", b = " << b << endl;

cout << "result = " << result << endl;

}

Please make comments as you go through so i can understand. thankyou.

Answer 1

answer:

int function1( int x, int& y) the value of A passed into x and y is reference variable of B

{

if( x % 2 == 0) /* condition checked value using passed by A into X*/

{

x = x + y;

   }

      y = y - x;

      return x;

}

int main() {

      int a, b, result;/* initializing variables */

cin >> a >> b;/* assigining values to variables */

result = function1(a, b);/* calling function*/

cout << "a = "<< a << ", b = " << b << endl;/* prints the updated values of a and b after the function called*/

cout << "result = " << result << endl;/* print the result value*/

}

output:

a = 4, b = -4 result = 12

taken a value 4 and b value 8

here after calling the function1 the values are passed as b is call by refrence hence the change in the value y also changes the value b hence as x%2==0 condition succed x=x+y is done and the result is x value which is returned.

while y is the y-x value as x value updated to 12 so 8-12 is -4 which is updated as it refrence to B. b will also change to -4 hence the above output is explained.