Array parameter sizeof, array parameter sizeof

Array parameter sizeof, array parameter sizeof

In the following code, when an array is used as a function parameter, the array size needs to be calculated in the function:

Void copy (int a [], int B []) {memcpy (B, a, sizeof ());}

This Code is intended to copy all the characters in a to B, but it will not be able to get the correct result at runtime. Because when an array is used as a form parameter, it is converted into a pointer in the function, so sizeof (a) returns the pointer size, not the size of array. The correct method is to reference the array as a parameter:

Void copy (int (& a) [], int B []) {memcpy (B, a, sizeof ());}