Find maximum and minimum | Kuchup interview prep

The 30 second answer

For a simple max I use stream max with natural order. When I also need count, sum, and average, I map to IntStream and call summaryStatistics in one pass. On an empty stream getMax returns Integer.MIN_VALUE, which is a trap worth calling out.

Optional<Integer> max = nums.stream().max(Comparator.naturalOrder());

IntSummaryStatistics st = nums.stream()
    .mapToInt(Integer::intValue)
    .summaryStatistics();
st.getMax();
st.getMin();

summaryStatistics() gives count, sum, min, max, and average in one pass. On empty input getMax() returns Integer.MIN_VALUE and getMin() returns Integer.MAX_VALUE — mention that trap.

Sources:

IntSummaryStatistics
Stream.max

Sources (0)

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