GATE CSE 2017 Set 2 | Question: 14

Question

Consider the following function implemented in C:

void printxy(int x, int y) {
    int *ptr;
    x=0;
    ptr=&x;
    y=*ptr;
    *ptr=1;
    printf(“%d, %d”, x, y);
}

The output of invoking $printxy(1,1)$ is:

• A. $0, 0$
• B. $0, 1$
• C. $1, 0$
• D. $1, 1$

Comments

already solved

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Answer will be (c). x=1,y=0

Answer 1

Option C: 1,0

 

Answer 2

Option c is right.

Answer 3

Explanatin:

initially x and y are passed into this function using call by value printxy(1,1)

X is 1 

y is 1

now what you are doing is assigning x=0 

 

now x=0 y=1

PTR is pointing to x means it has x’s address

x’s value is now copied into y

x=0 and y=0

*ptr=1 means you are assigning value 1 to x

now x=1, y=0

Option C