[Study Notes] [C Language] sizeof, Study Notes sizeof

[Study Notes] [C Language] sizeof, Study Notes sizeof

1. used to calculate the memory bytes occupied by a variable, a constant, or a data type.

2. sizeof has three forms

1> sizeof (variable \ constant)

Sizeof (10); char c = 'a'; sizeof (c );

2> sizeof variable \ constant

Sizeof 10; char c = 'a'; sizeof c;

3> sizeof (data type)

Sizeof (float );

Note: it cannot be written as sizeof float;

3. Code

1 # include <stdio. h> 2 3 int main () 4 {5 // int size = sizeof (10); 6 // int size = sizeof 10.9; 7 8 int a = 10; 9 10 // int size = sizeof (a); 11 // int size = sizeof a; 12 13 int size = sizeof (char); 14 // int size = sizeof char; // The error code 15 16 printf ("size = % d \ n", size); 17 18 return 0; 19}