c - Why &a is illegal l-value and why it is used in scanf() function then -



c - Why &a is illegal l-value and why it is used in scanf() function then -

i'm studying pointers in c, , i'm finding topics confusing. searched google , particular site not understand them.

i have questions regarding forms variable take:

1) difference between a=2 , &a=2 ? 2) why &a used l-value illegal?

as far understand, &a=2; illegal , &a illegal l-value because &a contains memory address not memory contents. , since memory address in form of integer hence can't assign value integer.

3) happens in scanf() function then?

i mean if take illustration scanf("%d",&a);. why &a used here, why not *(&a). why compiler not show kind of error?

please please help , explain :)

you cannot assign value &a, because &a denotes address variable a stored, , address determined 1 time , @ programme start , can't changed.

when using scanf, want 1 or more variables modified scanf function. hence must pass address of variables modified scanf.

c

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