pass_by_ref.cpp

#include <iostream>
using namespace std;

/*
	Define a function CoordTransform() that transforms its first two input parameters xVal and yVal into two output parameters xValNew and yValNew. The function returns void. The transformation is new = (old + 1) * 2. Ex: If xVal = 3 and yVal = 4, then xValNew is 8 and yValNew is 10.
*/

/* Your solution goes here  */
//void CoordTransform(int xVal, int yVal, int &xValNew, int &yValNew){ 	//<-- wrong!
void CoordTransform(int xVal, int yVal, int &xValNew, int &yValNew){		//<-- right!
	/* Forgetful error: Line above
	 * Forgetting to use &xValNew instead of *xValNew
	 */
	xValNew = (xVal + 1) * 2;
	yValNew = (yVal + 1) * 2;
}

int main(){
   int xValNew = 0;
   int yValNew = 0;

   CoordTransform(3, 4, xValNew, yValNew);
   cout << "(3, 4) becomes " << "(" << xValNew << ", " << yValNew << ")" << endl;

   return 0;
}