A question about array assignment in C

Array assignment I would like to sum up three types, the char example:

 

Assign values directly when defining.

1: Char A [20] = "Hello world! ";

 

2: Char A [20];

Strcpy (a, "Hello world! ");

 

3: Char A [20] = {'h', 'E', 'l', 'l', 'O', '', 'w', 'O ', 'R', 'l', 'D ','! '};

 

Common error Assignment Methods:

 

1: Char A [20];

A = "Hello world! ";

 

Cause: first, a char array with a length of 20 is defined, that is, 20 consecutive units are opened in the stack during runtime, and a is the first address of 20 units.

Next, heap a string "Hello world! ", Assign the landlord of this string to A, and a is the address of 20 consecutive units. So this time is messy. You cannot assign values like this.