added solution and test case for 128 (fishercoder1534#151)

ashmichheda · web-flow · commit 5ab7cd54f373 · 2021-02-23T18:51:10.000-08:00
diff --git a/src/main/java/com/fishercoder/solutions/_128.java b/src/main/java/com/fishercoder/solutions/_128.java
@@ -113,4 +113,28 @@ public int longestConsecutive(int[] nums) {
       return max;
     }
   }
+
+  public static class Solution3 {
+    public int longestConsecutive(int[] nums) {
+      HashSet<Integer> numSet = new HashSet<>();
+      for (int num : nums) {
+        numSet.add(num);
+      }
+
+      int longestStreak = 0;
+      for (int num : nums) {
+        if (!numSet.contains(num - 1)) {
+          int currentNum = num;
+          int currentStreak = 1;
+
+          while (numSet.contains(currentNum + 1)) {
+            currentNum += 1;
+            currentStreak += 1;
+          }
+          longestStreak = Math.max(longestStreak, currentStreak);
+        }
+      }
+      return longestStreak;
+    }
+  }
 }
diff --git a/src/test/java/com/fishercoder/_128Test.java b/src/test/java/com/fishercoder/_128Test.java
@@ -0,0 +1,24 @@
+package com.fishercoder;
+
+import com.fishercoder.solutions._128;
+import org.junit.BeforeClass;
+import org.junit.Test;
+
+import static org.junit.Assert.assertEquals;
+
+public class _128Test {
+    private static _128.Solution3 solution3;
+    private static int[] nums;
+
+    @BeforeClass
+    public static void setup() {
+        solution3 = new _128.Solution3();
+    }
+
+    @Test
+    public void test1() {
+        nums = new int[]{100,4,200,1,3,2};
+        int result = 4;
+        assertEquals(4, solution3.longestConsecutive(nums));
+    }
+}
