C program to swap two numbers without using third variable and using functions

• C program to swap two numbers using functions temporary variable.
• We can swap two numbers by using temporary variable.
•  Lets see an example C program to swap two numbers without using any function.
• C program to swap two numbers using third variable

Program #1: Write a C program to swap two numbers using temporary variable without using any function and by using third variable.

1. #include <stdio.h>
2. #include <stdlib.h>
3.  
4. int main(int argc, char *argv[])
5. {
6.   int a,b, temp;
7.   printf("Please enter two integer number to swap\n");
8.   scanf("%d%d",&a,&b);
9.   printf("before swapping\n");
10.   printf("a=%d\n",a); 
11.   printf("b=%d",b);   
12.   temp=a;
13.   a=b;
14.   b=temp;
15.   printf("\nafter swapping\n");
16.   printf("a=%d\n",a); 
17.   printf("b=%d",b);        
18.   
19.  return 0;
20.   
21. }
     

 Output:

Program #2: Write a C program to swap two numbers using temporary variable with using  function and using third variable.

• C program to swap two numbers using functions call by value

1. #include <stdio.h>
2. #include <stdlib.h>
3. void swap(int a, int b);
4. int main(int argc, char *argv[])
5. {
6.   int a,b;
7.   printf("Please enter two integer numbers to swap\n");
8.   scanf("%d%d",&a,&b);
9.   printf("before swapping\n");
10.   printf("a=%d\n",a); 
11.   printf("b=%d",b);   
12.   
13.   swap(a,b);   
14.     
15.   return
16.   
17. }
18.  
19. void swap(int a, int b){
20.     
21.   int temp=a;
22.   a=b;
23.   b=temp;
24.   printf("\nafter swapping\n");
25.   printf("a=%d\n",a); 
26.   printf("b=%d",b); 
27.     
28. }

Output:

1. Please enter two integer numbers to swap
2. 10
3. 20
4. before swapping
5. a=10
6. b=20
7. after swapping
8. a=20
9. b=10