c - Pointers addresses behaviour -

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this question has answer here:

for example:

int *ptr

what's difference beetween &ptr , ptr because when 

printf("ptr= %d  &ptr=%d",ptr,&ptr);

the result not same.

ptr pointer value (it's address).

&ptr address of pointer object.

to print pointer value have use:

printf("ptr= %p  &ptr=%p", (void *) ptr, (void *) &ptr);

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