Codeforces Round #784 (Div. 4) 1669 C. Odd/Even Increments Solution

Problem link:  https://codeforces.com/contest/1669/problem/C

Solution in C++:  

 ///La ilaha illellahu muhammadur rasulullah

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

///Abul Hasnat  Tonmoy

///Department of CSE,23rd batch

///Islamic University,Bangladesh

///**********ALLAH IS ALMIGHTY************///

#include <bits/stdc++.h>

using namespace std;

int main()

{

    long long i, n,x,y,t,f;

    cin>>t;

    while(t--)

    {

        cin>>n;

        int a[n+9];

        f=0;

        for(i=1; i<=n; i++)

        {

            cin>>a[i];

            x=a[1]%2;

            y=a[2]%2;

        }

        for(i=3; i<=n; i++)

        {

            if(i%2==1)

            {

                if(a[i]%2!=x)

                {

                    f=1;

                    break;

                }

            }

            else

            {

                if(a[i]%2!=y)

                {

                    f=1;

                    break;

                }

            }

        }

        if(f==0)

            cout<<"YES"<<endl;

        else

            cout<<"NO"<<endl;

    }

}