This approach could work, but it becomes less efficient as the number of gaps increase in both frequency and size. More importantly, it is also much trickier to insert a new element or change the order of the elements. I realize that neither insertion nor reordering were specified requirements in the OP, but I was trying to generalize the solution and anticipate future needs*. A linked list would handle those requirements easily.

*I've never been part of a project that hasn't had some degree of feature creep, and this one seems likely. "Oh, good - we can delete pictures. Hey, can we add them, too?"

In reply to Re^3: finding next key in db_file by bobf
in thread finding next key in db_file by Anonymous Monk

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