prgressing longestConsecutive

Author: geegong

longest-consecutive-sequence/Geegong.java

@@ -0,0 +1,42 @@
+import java.util.HashSet;
+import java.util.Iterator;
+
+public class Geegong {
+
+    public int longestConsecutive(int[] nums) {
+
+        HashSet<Integer> setOfNums = new HashSet<>();
+        int start = 0;
+        int end = 0;
+
+        // initialize
+        for (int num : nums) {
+            setOfNums.add(num);
+            start = Math.min(start, num);
+            end = Math.max(end, num);
+        }
+
+        Integer longest = 0;
+        Integer current = 0;
+        while (start <= end) {
+
+            iterate(setOfNums, start, current);
+            longest = Math.max(longest, current);
+        }
+    }
+
+    public Integer iterate(HashSet<Integer> hashSet, Integer start, Integer currentLength) {
+
+        if (hashSet.contains(start)) {
+            currentLength++;
+            iterate(hashSet, start+1, currentLength);
+
+        } else {
+            // currentLength 를 리턴해야 하나..
+            return start;
+        }
+
+    }
+
+}
+