Problem Solving Through C (BCA) 1st Sem Previous Year Solved Question Paper 2022

Pass by Value:

• In this method, a copy of the actual parameter is passed to the function. Changes made to the parameter inside the function do not affect the original value.

• This is the default method for passing parameters in C.

Example:

#include <stdio.h>

 

void modifyValue(int x) {

x = x * 2; // Changes made to x don't affect the original value

}

int main() {

int value = 5;

modifyValue(value);

printf("Original value: %d\n", value); // Output: Original value: 5

return 0;

}

Pass by Pointer:

• In this method, a pointer to the actual parameter is passed to the function. Changes made to the parameter inside the function affect the original value.

Example:

#include <stdio.h>

void modifyValue(int *x) {

*x = *x * 2; // Changes made to *x affect the original value

}

int main() {

int value = 5;

modifyValue(&value);

printf("Original value: %d\n", value); // Output: Original value: 10

return 0;

}

Pass by Reference (Not Native to C, Simulated Using Pointers):

• C doesn't have true pass-by-reference, but you can simulate it by passing a pointer to a variable.

• This allows changes made to the parameter inside the function to affect the original value.

Example:

#include <stdio.h>

void modifyValue(int &x) { // Simulated pass-by-reference

x = x * 2;

}

int main() {

int value = 5;

modifyValue(value);

printf("Original value: %d\n", value); // Output: Original value: 10

return 0;

}