我试图了解范围界定的不同之处：
//global scope
int size = 4;
int array[size]; // error: variably modified 'array' at file scope
int main(void) {
int buff[size]; // works!
}
how does using a variable as array size doesn't work globally but works inside main? It would work if I use a macro instead.
Also, does using const matter for size?
