This document contains code examples and questions about functions in C programming. It demonstrates passing arguments to functions by value and by address, as well as recursion using a factorial function. The code samples show how arguments are passed differently depending on whether they are passed by value or by reference. The factorial function recursively calls itself to calculate the factorial of a given number.

1. UNIVERSITI TUN HUSSEIN ONN MALAYSIA
FACULTY OF MECHANICAL AND MANUFACTURING ENGINEERING
BTI 10202: COMPUTER PROGRAMMING
LAB 10 : Functions (cont)
NAME : _____________________________________
MATRICS NO.: _______________ DATE : ____________ MARK
Exercise 1: Type the coding below and answer the following questions:
1 #include<stdio.h>
2 #include<conio.h>
3 void swapByValue(int a, int b );
4 void swapByAddress(int *a, int *b );
5
6 void swapByValue(int a, int b ){
7 int temp;
8 Temp = a;
9 a = b;
10 b = temp;
11
12 }
13 void swapByAddress(int *a, int *b ){
14 int temp;
15 temp = *a;
16 *a = *b;
17 *b = temp;
18
19 }
20 int main(void){
21 int a, b;
22 a = 8, b = 5;
23
24 printf("nIntially a=%3d and b=%3d ", a, b);
25 swapByValue(a, b);
26 printf("nAfter swap by value a=%3d and b=%3d", a, b);
27 swapByAddress(&a, &b);
28 printf("nAfter swap by address a=%3d and b=%3d", a, b);
29 getch();
30 return 0;
31}
i. What is the output of the coding? Output:

2. ii. Explain the difference between passing by value and address
By value: ________________________________________________________
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By Address: ______________________________________________________
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iii. Add printf("nnIn swap by value function a=%3d and b=%3d", a, b); at line 11
Add printf("nnIn swap by address a=%3d and b=%3d", *a, *b); at line 18
What is the output of the coding? Explain:
By value: ________________________________________________________
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By Address: ______________________________________________________
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3. Exercise 2 : Type the coding below and answer the following questions:
#include <stdio.h>
#include <conio.h>
main ()
{
int n;
long faktorial ( int );
printf("Enter n (1-15): ");
scanf ("%d",&n);
printf ("%d! = %dn",n, faktorial ( n ) );
getch();
}
long faktorial ( int n ) {
if ( n == 0 )
return 1;
else
return (n * faktorial ( n -1 ));
}
i. What is the output of the coding? Output:
ii. Explain how the coding work (input: 3) :
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