#include <bits/stdc++.h>   using namespace std;   long long a[100010];   bool b[100010];   long long gcd(long long a, long long b) { return a % b ? gcd(b, a % b) : b; }   int main() {     long long n, t;     scanf( %lld , &n);     for (int i = 1; i <= n; i++) {       scanf( %lld , &a[i]);       b[i] = a[i] % 2;     }     long long ans = gcd(abs(a[1]), abs(a[2]));     for (int i = 3; i <= n; i++) ans = gcd(ans, abs(a[i]));     if (ans > 1)       printf( YES n0 n );     else {       int num = 0;       for (int i = 1; i < n; i++)         while (b[i] == 1) {           if (b[i + 1] == 1) {             b[i] = 0;             b[i + 1] = 0;           } else {             b[i + 1] = 1;           }           ++num;         }       if (b[n] == 1) num += 2;       printf( YES n%d n , num);     }     return 0;   }   