#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
const ll N = 1e3 + 5;
ll n, a[N]; 
bool check(ll x){
	ll js = 0, os = 0;
	for(int i = 1; i <= n; i++){
		if(!(a[i] % 2)){
			os++;
		}else{
			js++;
		}
	}
	ll ans = os * 2 + js - (ll)ceil(x / 2.0) * 2 - x / 2;
	return ans >= 0 && ans % 2 == 0 && js >= x / 2;
}
int main(){
	cin >> n;
	for(int i = 1; i <= n; i++){
		cin >> a[i];
	}
	for(int i = n; i >= 1; i--){
		if(check(i)){
			cout << i;
			break;
		}
	}
	return 0;
}

本人觉得挺玄学,求大佬解释。