Create keep-multiplying-found-values-by-two.cpp

Author: kamyu104

C++/keep-multiplying-found-values-by-two.cpp

@@ -0,0 +1,12 @@
+// Time:  O(n)
+// Space: O(n)
+
+// hash table
+class Solution {
+public:
+    int findFinalValue(vector<int>& nums, int original) {
+        unordered_set<int> lookup(cbegin(nums), cend(nums));
+        for (; lookup.count(original); original *= 2);
+        return original;
+    }
+};