Added New Java file in Java/Misc

TheAlgorithms · AzadN · Nov 4, 2020 · Nov 4, 2020 · Nov 4, 2020 · Nov 4, 2020
commit 0172c299c7cb3394ff8700c71c2cc00d24451994
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) // Store longest range at every interation
+                longestRange = currentRange;
+        }
+        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}
+    }
+}