What does swap mean in c language?

The swap function is used in C language to exchange the values ​​of two variables. Its function prototype is void swap(int a, int b), where a and b are two integer pointers pointing to the two variables whose values ​​need to be exchanged. Value exchange can be achieved by calling the swap function and passing the variable address.

The meaning of swap in C language

swap is a function in C language, used to exchange two the value of a variable. The function prototype is:

<code>void swap(int *a, int *b);</code>

Among them, a and b are two integer pointers, pointing to the two variables that need to exchange values.

How to use the swap function

To use the swap function to exchange the values ​​​​of two variables, you can follow the following steps:

1. Declare two integer variables a and b, and initialize their values.
2. Call the swap function and pass the addresses of a and b as parameters to the function.
3. After the exchange is completed, the values ​​of a and b will be exchanged.

Example

The following code snippet demonstrates how to use the swap function:

<code>#include <stdio.h>

int main() {
  int a = 10;
  int b = 20;

  printf("Before swap: a = %d, b = %d\n", a, b);

  swap(&a, &b);

  printf("After swap: a = %d, b = %d\n", a, b);

  return 0;
}</code>

The output result is:

<code>Before swap: a = 10, b = 20
After swap: a = 20, b = 10</code>

Working principle

The swap function uses pointers to exchange the values ​​of variables. The pointer passed to the swap function points to the variable whose value is to be swapped. Inside the function, it uses the indirect addressing operator (*) to access variables and exchange their values.

Notes

When using the swap function, you need to pay attention to the following:

• a and b must be variables of the same type.
• a and b must be variables, not constants or expressions.
• The addresses of a and b must be valid.

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