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#include <iostream>
#include <ctime>
typedef long long ll;
using namespace std;
ll gt(int n){
if(n==0) return 1;
return n*gt(n-1);
}
ll th(int k, int n){
ll s = 1;
for(int i = n-k+1; i <= n; i++)
s *= i;
return s/gt(k);
}
int main(){
freopen("quick.inp","r",stdin);
freopen("quick.out","w",stdout);
int c, l = 0;
int n; cin >> n;
for(int i = 0; i < n; i++){
int t; cin >> t;
if(t%2 != 0) ++l;
}
c = n-l;
if(l%2 == 0) cout << th(2,c)+th(2,l) << endl;
else cout << 1ll*c*l << endl;
return 0;
}
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