Code RoomInteger map boxing on primitives
HardPrep Room Coding #1933

Integer map boxing on primitives

Code reviewCode quality & reviewSenior–Staff~22 min

Review this Java method that counts occurrences of each integer key in a high-volume stream of events.

What a strong answer looks like

Separate real bugs from style. Rank issues by severity, point at the root cause rather than the symptom, and suggest a concrete fix, specific and kind.

0:00 of about 22 min
Mark a line and say what kind of problem it is.0 findings
1Map<Integer, Integer> countKeys(int[] keys) {
2 Map<Integer, Integer> counts = new HashMap<>();
3 for (int k : keys) {
4 Integer cur = counts.get(k);
5 counts.put(k, cur == null ? 1 : cur + 1);
6 }
7 return counts;
8}
Which questions mattered is sealed until you submit. Telling you now would just be handing over the edge cases.