Longest Consecutive Sequence

Author: eunhwa99

longest-consecutive-sequence/eunhwa99.java

@@ -0,0 +1,23 @@
+import java.util.HashSet;
+
+class Solution {
+    public int longestConsecutive(int[] nums) {
+        HashSet<Integer> mySet = new HashSet<Integer>();
+
+        for (int num : nums) {
+            mySet.add(num);
+        }
+
+        int result = 0;
+        for (int num : mySet) {
+            int cnt = 1;
+            if (!mySet.contains(num - 1)) {
+                while (mySet.contains(++num)) {
+                    ++cnt;
+                }
+                result = Math.max(cnt, result);
+            }
+        }
+        return result;
+    }
+}