Method updateFrequency

java/0460-lfu-cache.java:47–59

(Entry e)

    }

    private void updateFrequency(Entry e) {
        int oldFreq = e.freq;
        int newFreq = oldFreq + 1;

        freqMap.get(oldFreq).remove(e);
        if (freqMap.get(oldFreq).isEmpty()) {
            freqMap.remove(oldFreq);
            if (minFreq == oldFreq) minFreq++;
        }

        e.freq = newFreq;
        freqMap.computeIfAbsent(newFreq, k -> new LinkedHashSet<>()).add(e);
    }

    private void evictLeastFrequent() {
        LinkedHashSet<Entry> minFreqEntries = freqMap.get(minFreq);