Mike has a sequence *A* = [*a*<sub class="lower-index">1</sub>, *a*<sub class="lower-index">2</sub>, ..., *a*<sub class="lower-index">*n*</sub>] of length *n*. He considers the sequence *B* = [*b*<sub class="lower-index">1</sub>, *b*<sub class="lower-index">2</sub>, ..., *b*<sub class="lower-index">*n*</sub>] beautiful if the *gcd* of all its elements is bigger than 1, i.e. <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/1829934399ec1245c6050a62cf6e36810163b03b.png" style="max-width: 100.0%;max-height: 100.0%;"/>. 

Mike wants to change his sequence in order to make it beautiful. In one move he can choose an index *i* (1 ≤ *i* &lt; *n*), delete numbers *a*<sub class="lower-index">*i*</sub>, *a*<sub class="lower-index">*i* + 1</sub> and put numbers *a*<sub class="lower-index">*i*</sub> - *a*<sub class="lower-index">*i* + 1</sub>, *a*<sub class="lower-index">*i*</sub> + *a*<sub class="lower-index">*i* + 1</sub> in their place instead, in this order. He wants perform as few operations as possible. Find the minimal number of operations to make sequence *A* beautiful if it's possible, or tell him that it is impossible to do so.

<img align="middle" class="tex-formula" src="https://espresso.codeforces.com/69b4319fc56f0d760506d7f84e7647ff65f6bdc5.png" style="max-width: 100.0%;max-height: 100.0%;"/> is the biggest non-negative number *d* such that *d* divides *b*<sub class="lower-index">*i*</sub> for every *i* (1 ≤ *i* ≤ *n*).
The first line contains a single integer *n* (2 ≤ *n* ≤ 100 000) — length of sequence *A*.

The second line contains *n* space-separated integers *a*<sub class="lower-index">1</sub>, *a*<sub class="lower-index">2</sub>, ..., *a*<sub class="lower-index">*n*</sub> (1 ≤ *a*<sub class="lower-index">*i*</sub> ≤ 10<sup class="upper-index">9</sup>) — elements of sequence *A*.
In the first example you can simply make one move to obtain sequence [0, 2] with <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/6ddb490b8e898198d30c56c6edce2cf15e6f998a.png" style="max-width: 100.0%;max-height: 100.0%;"/>.

In the second example the *gcd* of the sequence is already greater than 1.
2
1 1
YES
1
3
6 2 4
YES
0
2
1 3
YES
1
9
57 30 28 81 88 32 3 42 25
YES
8
2
8 77
YES
2
4
92 46 3 21
YES
1
2
78 26
YES
0
2
3 6
YES
0
2
3 9
YES
0
2
3 3
YES
0
3
3 6 3
YES
0
3
3 9 15
YES
0
3
3 6 9
YES
0
3
3 3 3
YES
0
3
3 9 18
YES
0
5
1 2 1 2 1
YES
6
2
9 6
YES
0
4
3 6 9 12
YES
0
3
3 9 27
YES
0
3
3 9 12
YES
0
5
6 6 9 15 21
YES
0
2
5 15
YES
0
4
2 3 9 13
YES
3
4
3 3 3 3
YES
0
5
3 9 9 9 27
YES
0
2
9 9
YES
0
3
3 9 9
YES
0
3
7 14 21
YES
0
3
3 12 4
YES
2
5
3 3 3 3 3
YES
0
from math import gcd
n = int(input())
a = list(map(int, input().split()))
g = a[0]
for i in range(n):
    g = gcd(g, a[i])
if g > 1:
    print('YES')
    print(0)
    exit(0)
a.append(0)
b = []
for i in range(n):
    a[i] %= 2
cnt = 1
for i in range(1, n + 1):
    if a[i] != a[i - 1] and a[i - 1] == 1:
        b.append(cnt)
        cnt = 1
    elif a[i] == 1:
        cnt += 1



print('YES')
ans = 0
for i in b:
    ans += i // 2
    if i % 2 == 1:
        ans += 2
print(ans)


