c - Why is the address operator (&) important for an array being passed through a function? -


i having trouble understanding how & operator works , importance.

i found example online:

 #include <stdio.h>  void main() {   int = 10;   printf("\nvalue of n : %d" ,n);   printf("\nvalue of &n : %u", &n); }

output :

value of  n : 10 value of &n : 1002

firstly, why &n print out 2 numbers?

secondly, why important?

n variable. represents value.
&n reference n. represents address in memory n store.

as why important:

when pass array in c, function expecting pointer. (ie: int* opposed int).
if pass 'n' function, complain when compiling because types don't match (n=int, function expects int*).
if pass in &n, passing in address 'n' function expects.


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