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c - Difference between *ptr[10] and (*ptr)[10]

For the following code:

    int (*ptr)[10];
    int a[10]={99,1,2,3,4,5,6,7,8,9};
    ptr=&a;
    printf("%d",(*ptr)[1]);

What should it print? I'm expecting the garbage value here but the output is 1.
(for which I'm concluding that initializing this way pointer array i.e ptr[10] would start pointing to elements of a[10] in order).

But what about this code fragment:

int *ptr[10];
int a[10]={0,1,2,3,4,5,6,7,8,9};
*ptr=a;
printf("%d",*ptr[1]);

It is giving the segmentation fault.

See Question&Answers more detail:os

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int *ptr[10];

This is an array of 10 int* pointers, not as you would assume, a pointer to an array of 10 ints

int (*ptr)[10];

This is a pointer to an array of 10 int

It is I believe the same as int *ptr; in that both can point to an array, but the given form can ONLY point to an array of 10 ints


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