Best method to create a sub array from an array in C

Question

I have an array say a[3]={1,2,5} . I have to create another array a2[2]={2,5}.

What I have tried is to just create a new array a2[] and just copy all the elements from the required position range.

Is there any other method to accomplish this in C?.

BLUEPIXY · Accepted Answer · 2013-07-20 15:09:17Z

36

memcpy(a2, &a[1], 2*sizeof(*a));

answered Jul 20, 2013 at 15:09

BLUEPIXY

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2 Comments

Shouldn't it be memcpy(&a2, &a[1], 2*sizeof(*a)); ?

No, a2 is already a pointer to array but a[i] is number instead.

ouah · Accepted Answer · 2013-07-20 14:51:23Z

28

Instead of having a second array, just use a pointer:

int a[3]={1,2,5};
int *p = &a[1];

If they have to be distinct, you have no choice other than to copy the array elements into a new array.

answered Jul 20, 2013 at 14:51

ouah

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