AtCoder Beginner Contest 073 C Write and Erase Solution

Problem Link:  https://atcoder.jp/contests/abc073/tasks/abc073_c 

Solution in C++:

///La ilaha illellahu muhammadur rasulullah

///******Bismillahir-Rahmanir-Rahim******///

///Abul Hasnat  Tonmoy

///Department of CSE,23rd batch

///Islamic University,Bangladesh

#include <bits/stdc++.h>

using namespace std;

int main()

{

    int n,x,y,t,s=0;

    map<int,int>mp;

    set<int>st;

    cin>>t;

    while(t--)

    {

        cin>>n;

        mp[n]++;

        st.insert(n);

    }

    for (auto it = st.begin(); it !=st.end(); ++it)

    {

      if(mp[*it]%2==1)

        s++;

    }

   cout<<s<<endl;

}