AppliedNumeric answer
A rolling mean, faster · Part 2 of 3
You compute a 50-day rolling mean over a list p of 1,000 prices, producing one value for each full window. Count one read each time a price is fetched from the list.
A running sum reads the first window once, then for each later window adds the price that enters and subtracts the one that leaves. How many reads does it make?
Answer with a number. Fractions, powers and expressions like 23/6 or C(52,5) are read correctly in practice.
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