Memory allocation of variable arrays in c

Question

Is the memory to variable arrays allocated during run-time or compile-time in c?

int n; 
printf("Enter size of the array: ");
scanf("%d",&n);

int a[n];
for(int i=0; i<n; i++)
   {
      a[i] = 0;
   }
}

Just an (off-topic) note for you: this is not the standard in C++ - you'd want to use a vector. — Matt
– Matt, Commented Feb 18, 2015 at 17:10

JuniorCompressor · Accepted Answer · 2015-02-18 16:58:24Z

2

Since the size n of the array is defined at runtime, then also the allocation happens in the runtime.

The memory is allocated from the stack, which is faster than allocating from the heap. But how much memory you can reserve is much lower.

answered Feb 18, 2015 at 16:58

JuniorCompressor

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Comments

haccks · Accepted Answer · 2015-02-18 16:58:11Z

1

It is allocated on run time but on stack not on heap.

answered Feb 18, 2015 at 16:58

haccks

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