A Classic C Programming Mistake - See if You Can Spot it

size_t *sz_out;

*sz_out = input[sz_in-1] - input[0]+1;

int * output = (int *) malloc( *sz_out );

Nail it?  That's right, you have to be specific in the malloc call. If you give it just a number (in this case, sz_out is a number of bytes - size of output) it'll allocate that many bytes - not what you want. 

You always use malloc along with the sizeof operator to get the allocation right.

Live and learn.

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