Problem: You are given an array of n elements, you must make it a co-prime array in as few moves as possible.

In each move you can insert any positive integral number you want not greater than 109 in any place in the array.

An array is co-prime if any two adjacent numbers of it are co-prime.

In the number theory, two integers a and b are said to be co-prime if the only positive integer that divides both of them is 1.

Input

The first line contains integer n (1 ≤ n ≤ 1000) — the number of elements in the given array.

The second line contains n integers ai (1 ≤ ai ≤ 109) — the elements of the array a.

Output

Print integer k on the first line — the least number of elements needed to add to the array a to make it co-prime.

The second line should contain n + k integers aj — the elements of the array a after adding k elements to it. Note that the new array should be co-prime, so any two adjacent values should be co-prime. Also the new array should be got from the original array a by adding k elements to it.

If there are multiple answers you can print any one of them.

Example

Input

3
2 7 28


Output

1
2 7 9 28

Solution (in PYTHON3):

Solution:
# all number 1~1e9

def gcd(a,b):
    while b != 0:
        t = b
        b = a % b
        a = t
    return a

def coprime(a,b):
    if gcd(a,b) == 1:
        return True
    else:
        return False

def isPrime(n):
    if (n <= 1): return False
    if (n <= 3): return True

    # This is checked so that we can skip
    # middle five numbers in below loop
    if (n % 2 == 0 or n % 3 == 0): return False

    i = 5
    while (i * i <= n):
        if (n % i == 0 or n % (i + 2) == 0):
            return False
        i = i + 6
    return True

# find a number coprime with both inputs
def find_coprime(a,b,primelist):
    for p in primelist:
        if (coprime(p,a) and coprime(p,b)):
            return p

    n = len(primelist)
    p = primelist[n-1]+2 # last prime is odd
    while True:
        if not isPrime(p):
            p += 2
        primelist.append(p)
        if (coprime(p, a) and coprime(p, b)):
            return p
        p += 2
    return p

def coprime_array(a,b,primelist):
    n = len(a)
    k = 0
    if n == 1:
        b.append(a[0])
        return k

    for i in range(n):
        if i == n - 1:
            b.append(a[i])
            break

        b.append(a[i])
        if not coprime(a[i], a[i + 1]):
            b.append(find_coprime(a[i], a[i + 1], primelist))
            k += 1
    return k



n = int(input())
a = [int(x) for x in input().split()]
primelist = [2,3,5,7]
b = []
k = coprime_array(a,b,primelist)

print(k)
print(*b, sep=' ')