C语言 将指针传递给函数

#include <stdio.h>
void salaryhike(int  *var, int b)
{
    *var = *var+b;
}
int main()
{
    int salary=0, bonus=0;
    printf("Enter the employee current salary:"); 
    scanf("%d", &salary);
    printf("Enter bonus:");
    scanf("%d", &bonus);
    salaryhike(&salary, bonus);
    printf("Final salary: %d", salary);
    return 0;
}

Enter the employee current salary:10000
Enter bonus:2000
Final salary: 12000

#include <stdio.h>
void swapnum(int *num1, int *num2)
{
   int tempnum;

   tempnum = *num1;
   *num1 = *num2;
   *num2 = tempnum;
}
int main( )
{
   int v1 = 11, v2 = 77 ;
   printf("Before swapping:");
   printf("\nValue of v1 is: %d", v1);
   printf("\nValue of v2 is: %d", v2);

   /*calling swap function*/
   swapnum( &v1, &v2 );

   printf("\nAfter swapping:");
   printf("\nValue of v1 is: %d", v1);
   printf("\nValue of v2 is: %d", v2);
}

Before swapping:
Value of v1 is: 11
Value of v2 is: 77
After swapping:
Value of v1 is: 77
Value of v2 is: 11