TheAlgorithms · AzadN · Nov 4, 2020 · Nov 4, 2020 · Nov 4, 2020 · Nov 4, 2020
diff --git a/Misc/largestRange.java b/Misc/largestRange.java
@@ -0,0 +1,46 @@
+import java.util.*;
+
+public class largestRange {
+
+  // Finds the length of longest occurring consecutive numbers range in an array
+  public static int longestRange(int[] nums) {
+    int longestRange = 0;
+    HashMap<Integer, Boolean> num = new HashMap<>();
+
+    /**
+     * Stores a mapping of a number to whether the current number is part of a particular
+     * consecutive range or not.
+     */
+    for (int x : nums) num.put(x, true);
+    for (int x : nums) {
+      if (!num.get(x)) continue;
+      num.replace(x, false);
+      int currentRange = 1;
+      int left = x - 1;
+      int right = x + 1;
+      while (num.containsKey(left)) { // Search leftwards for consecutive range
+        num.replace(left, false);
+        currentRange += 1;
+        left--;
+      }
+      while (num.containsKey(right)) { // Search rightwards for consecutive range
+        num.replace(right, false);
+        currentRange += 1;
+        right++;
+      }
+      if (currentRange > longestRange)
+        longestRange = currentRange; // Store longest range at every interation
+    }
+    return longestRange;
+  }
+
+  public static void main(String[] args) {
+    // Testcases
+    assert longestRange(new int[] {1, 2, 3, 4, -1, 11, 10}) == 4;
+    // The longest consecutive number range is of length 4 i.e. {1, 2, 3, 4}
+    assert longestRange(new int[] {-1, 1, 3, 5, 7}) == 1;
+    // The longest consecutive number range is of length 1 i.e. any of the element alone
+    assert longestRange(new int[] {0, 1, 2, 3, 4, 7, 6, 5}) == 8;
+    // The longest consecutive number range is of length 8 i.e. {0, 1, 2, 3, 4, 5, 6, 7}
+  }
+}