in reply to Tracking minimum of values in an array over time
You can use a priority queue, such as a binary heap (Not necessarily that implementation, just something similar.) You keep the indices and values of your array in this priority queue, with lowest values down. Whenever you change a number in the array, you delete the corresponding entry from the priority queue and then reinsert a new one. The priority queue will then keep track of the element with the lowest value for you.
Re^2: Tracking minimum of values in an array over time by tj_thompson (Monk) on Oct 06, 2011 at 22:01 UTC 
A min heap would be an excellent way to determine the min value of the set at any time. Good call. For my particular problem, since I'm actually interested in making certain that all elements have crossed the floor value (as pointed out by Ant above), I think counting the number of values that cross the floor as they are incremented is the smartest solution.
Good thoughts Ambrus, thanks!
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