Codeforces

627A.cpp

#include<bits/stdc++.h>
 
#define endl "\n";
using namespace std;
typedef long long ll;
 
int arr[200001], inf = 1000000000;
 
int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
 
  int t; cin >> t;
  while (t--) {
    int n, maxi=0;
    cin >> n;
    vector<int> vc;
    for (int i = 0; i < n; i++) {
      int x; cin >> x;
      maxi = max(maxi, x);
      vc.push_back(x);
    }
    bool ans = true;
    for (int i = 0; ans && i < n; i++) {
      if ((maxi - vc[i]) % 2)ans = false;
    }
    if (ans) { cout << "YES" << endl; }
    else {cout << "NO" << endl;}
  }
}