C++: Assume given the following definition of function process: void process(int

Question

C++: Assume given the following definition of function process:
void process(int vnum, int & rnum1, int & rnum2)
{
vnum = vnum + 5;
rnum1 = rnum1 + 10;
rnum2 = vnum + rnum1;
}
And that local variables are defined in function main as follows:
int num1 = 10, num2 = 15, num3 = 20;
Indicate whether each of the following calls of function process is valid or invalid and:
For each invalid call, provide the reason why it is invalid.
Do the following for each valid call:
i. show the body of the function process in the way it is executed after the function call,
ii. then execute function process and show the contents of the variables num1, num2, and num3 after the function is executed.
a. process( num1, num2, num3 );
b. process( num2, num3, num1 );
c. process( num1, 10, num3 );

Explanation / Answer

a. process( num1, num2, num3 );

Explanation: Its a valid call. Here in this call num1 is passed as value and num2 and num3 are passed by reference. According to function decleration rnum1 and rnum2 are the reference variables. So after this function call we have following values:

num1 = 10 (Because num1 is passed by value, so its value will remain unchanged)
num2 = 25 (Because num2 is passed as reference and in the function we have rnum1 = rnum1 + 10 = 15 + 10 = 25)
num3 = 40 (Because num3 is passed as reference and in the function we have rnum2 = vnum + rnum1 = 15 +25 = 40)

b. process( num2, num3, num1 );

Explanation: Its a valid call. Here in this call num2 is passed as value and num3 and num1 are passed by reference. According to function decleration rnum1 and rnum2 are the reference variables. So after this function call we have following values:

num2 = 15 (Because num2 is passed by value, so its value will remain unchanged)
num3 = 30 (Because num3 is passed as reference and in the function we have rnum1 = rnum1 + 10 = 20 + 10 = 30)
num1 = 50 (Because num3 is passed as reference and in the function we have rnum2 = vnum + rnum1 = 20 +30 = 50)

c. process( num1, 10, num3 );

Explanation: Its a invalid call because here we are passing value 10 as second argument but in function we have used reference variable rnum1. So it will give compile error

Related Questions

Navigate

• Browse (All)
• Browse C
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.