Great Vova Wall (Version 1)

https://codeforces.com/contest/1092/problem/D1

/*
*@Author:   STZG
*@Language: C++
*/
#include <bits/stdc++.h>
#include<iostream>
#include<algorithm>
#include<cstdlib>
#include<cstring>
#include<cstdio>
#include<string>
#include<vector>
#include<bitset>
#include<queue>
#include<deque>
#include<stack>
#include<cmath>
#include<list>
#include<map>
#include<set>
//#define DEBUG
#define RI register int
using namespace std;
typedef long long ll;
//typedef __int128 lll;
const int N=200000+1000;
const int MOD=1e9+7;
const double PI = acos(-1.0);
const double EXP = 1E-8;
const int INF = 0x3f3f3f3f;
int t,n,m,k;
int a[N],q[N],top;
bool get(int x)
{
    top=0;
    for(int i=1;i<=x;i++){
       q[++top]=a[i];
       if(top>=2&&q[top]==q[top-1]) top-=2;
    }
    if(top<=1) return true;
    return false;
}
int main()
{
#ifdef DEBUG
	freopen("input.in", "r", stdin);
	//freopen("output.out", "w", stdout);
#endif
    scanf("%d",&n);
    for(int i=1;i<=n;i++) scanf("%d",&a[i]),a[i]=a[i]&1;
    if(get(n)) return puts("YES"),0;
    puts("NO");
    //cout << "Hello world!" << endl;
    return 0;
}