C++ :

#include <bits/stdc++.h>
using namespace std;

//根据奇数和偶数的数量计算分组数量 
int fun(int j,int o){
	int d = j - o; 
	if(d == 0) return j + o;
	else if(d == 1) return (j-2)*2+1;//return j + o - 2;
	else if(d == 2) return (j-2)*2+1;//return j + o - 1;
	else{
		j = j - 2;
		o = o + 1;
		return fun(j,o); 
	}
}

int n,j,o;
int main() {
	cin>>n;
	int x;
	for(int i = 1;i <= n;i++){
		cin>>x;
		if(x % 2 == 0) o++;
		else j++;
	}
	
	if(o > j) cout<<2*j + 1;
	else cout<<fun(j,o);
}