Problem:
Score : 200 points

Problem Statement

We will say that two integer sequences of length N, x_1, x_2, ..., x_N and y_1, y_2, ..., y_N, are similar when |x_i - y_i| \leq 1 holds for all i (1 \leq i \leq N).

In particular, any integer sequence is similar to itself.

You are given an integer N and an integer sequence of length N, A_1, A_2, ..., A_N.

How many integer sequences b_1, b_2, ..., b_N are there such that b_1, b_2, ..., b_N is similar to A and the product of all elements, b_1 b_2 ... b_N, is even?

Constraints

1 \leq N \leq 10

1 \leq A_i \leq 100

Input

Input is given from Standard Input in the following format:

N
A_1 A_2 ... A_N

Output

Print the number of integer sequences that satisfy the condition.

Sample Input 1

2
2 3

Sample Output 1

7

There are seven integer sequences that satisfy the condition:

1, 2

1, 4

2, 2

2, 3

2, 4

3, 2

3, 4

Sample Input 2

3
3 3 3

Sample Output 2

26

Sample Input 3

1
100

Sample Output 3

1

Sample Input 4

10
90 52 56 71 44 8 13 30 57 84

Sample Output 4

58921

Solution in Rust (1.15.1) (judge verdict: Wrong Answer)

use std::io;

fn main() {
  let stdin = io::stdin();
  let mut buf = String::new();  // 1
  stdin
      .read_line(&mut buf)
      .expect("ERROR Can't read array size");  // 2
  let size: usize = buf.trim().parse().unwrap();  // 3
  buf = String::new();  // 5
  stdin
      .read_line(&mut buf)
      .expect("ERROR Can't read input array");
  println!("{}", buf);
  let v: Vec<i64> = buf.split_whitespace() // 6
      .map(|n| n.parse().unwrap()) // 7
      .collect();

  let mut count = 1;
  let mut ans = 1;

  for i in 0..size {
    if v[i] % 2 == 0 {count = count * 2};
    ans = ans * 3;
  };

  ans = ans - count;

  println!("{}",ans);
}