Merge pull request #386 from ys13579/master

FindDuplicate.cpp

Author: probot-auto-merge[bot]

C++/FindDuplicate.cpp

@@ -0,0 +1,33 @@
+
+//Given numbers from 1 to n, find the duplicate number in 0(n) time complexity and O(1) space complexity
+
+
+class Solution {
+public:
+    int findDuplicate(vector<int>& nums) {
+        //Define an empty set
+        set<int> con;
+        set<int>::iterator it;
+        
+        //Iterate over the array
+        for(int i=0;i<nums.size();i++){
+            it = con.find(nums[i]);
+            
+            //Number already present in set
+            if(it != con.end())
+                return nums[i];
+            else
+                con.insert(nums[i]);
+        }
+   
+};
+
+int main() {
+   
+        vector<int> nums = {1, 2, 3, 7, 5, 6, 7}
+        
+        int ret = Solution().findDuplicate(nums);
+        cout << ret << endl;
+    
+        return 0;
+}