10-Find Duplicate in Array

#include <bits/stdc++.h>

int findDuplicate(vector<int> &arr, int n){
	// Write your code here.
	int ans=0;
	unordered_map<int,int> mp;
	for(int i=0;i<n;i++){
		mp[arr[i]]++;
	}

	for(auto i:mp){
		if(i.second>1){
			ans+=i.first;
		}
	}
	return ans;
}