memcpy() function. Memory copy is usually completed using the memcpy() function. The memcpy() function has three parameters:

1. dest: the pointer of the target memory, which is the location where the data is copied.

2. src: The pointer of the source memory, that is, the location from which the data is to be copied.

3. n: The number of bytes to be copied.

When calling the memcpy() function, pass the pointers to the source memory and target memory as the first two parameters, and the number of bytes to be copied as the third parameter