solves contains duplicate iii in java

Author: anishLearnsToCode

src/ContainsDuplicateIII.java

@@ -0,0 +1,51 @@
+import java.util.TreeMap;
+
+public class ContainsDuplicateIII {
+
+    public boolean containsNearbyAlmostDuplicate(int[] array, int k, int t) {
+        // no memory
+        if (k == 0) return false;
+
+        final TreeMap<Long, Integer> elements = new TreeMap<>();
+        for (int i = 0 ; i < array.length ; i++) {
+            long lowerBound = (long) array[i] - t;
+            long upperBound = (long) array[i] + t;
+            long lowerClosest = getClosestOrHigher(elements, lowerBound);
+            if (inRange(lowerClosest, lowerBound, upperBound)) return true;
+            long upperClosest = getClosestOrLower(elements, upperBound);
+            if (inRange(upperClosest, lowerBound, upperBound)) return true;
+            if (i >= k) {
+                removeFromMap(elements, array[i - k]);
+            }
+            addToMap(elements, array[i]);
+        }
+
+        return false;
+    }
+
+    private void removeFromMap(TreeMap<Long, Integer> elements, long val) {
+        if (elements.get(val) == 1) {
+            elements.remove(val);
+        } else {
+            elements.put(val, elements.get(val) - 1);
+        }
+    }
+
+    private void addToMap(TreeMap<Long, Integer> elements, long val) {
+        elements.put(val, elements.getOrDefault(val, 0) + 1);
+    }
+
+    private long getClosestOrHigher(TreeMap<Long, Integer> elements, long val) {
+        Long lowerClosest = elements.ceilingKey(val);
+        return lowerClosest == null ? Long.MAX_VALUE : lowerClosest;
+    }
+
+    private long getClosestOrLower(TreeMap<Long, Integer> elements, long val) {
+        Long upperClosest = elements.floorKey(val);
+        return upperClosest == null ? Long.MIN_VALUE : upperClosest;
+    }
+
+    private boolean inRange(long val, long low, long high) {
+        return low <= val && val <= high;
+    }
+}