Initial commit

Easy/contains-duplicate/solution.cpp

@@ -0,0 +1,19 @@
+class Solution {
+  public:
+    bool containsDuplicate(std::vector<int> &nums) {
+        std::unordered_set<int> unset;
+
+        int size = nums.size();
+        for (int i = 0; i < size; ++i) {
+            int occur = unset.count(nums[i]);
+
+            if (occur == 1) {
+                return true;
+            } else {
+                unset.insert(nums[i]);
+            }
+        }
+
+        return false;
+    }
+};