def Eratosthenes(N):
    isprime = [True for _ in range(N+1)]
    minfactor = [-1 for _ in range(N+1)]
    isprime[1] = False
    minfactor[1] = 1
    for p in range(2, N+1):
        if not isprime[p]:continue
        minfactor[p] = p
        for q in range(p*2, N+1, p):
            isprime[q] = False
            if minfactor[q]==-1:
                minfactor[q] = p
    primes = list()
    for p in range(2,N+1):
        if isprime[p]:
            primes.append(p)
    return primes


X = int(input())
tmp_prime = list()
if X!=1:
    primes = Eratosthenes(200000)
    while True:
        ok = False
        for i in primes:
            if X%i==0:
                ok = True
                X //= i
                tmp_prime.append(i)
                break
        if not ok:
            break
    #print(tmp_prime)
    #print("#", len(tmp_prime), sum(tmp_prime))
    prime = list()
    cnt_2 = 0
    for i in tmp_prime:
        if i==2:
            if cnt_2==1:
                prime.append(4)
                cnt_2 = 0
            else:
                cnt_2 += 1
        else:
            if cnt_2==1:
                prime.append(2)
                cnt_2 = 0
            prime.append(i)
    if cnt_2==1:
        prime.append(2)
    if X!=1:
        prime.append(X)
    #print(prime)
    #print("#", len(prime), sum(prime))
else:
    prime = [1]
if len(prime)+sum(prime)>2*10**5:
    print(-1)
    exit()
N = len(prime)+sum(prime)
G = [ [] for _ in range(N+1)]
idx = len(prime)
for i in range(1, len(prime)+1):
    for j in range(prime[i-1]):
        idx += 1
        G[i].append(idx)
print(N)
for i in range(1, len(prime)):
    G[i].append(i+1)
for i in range(1, N+1):
    for j in G[i]:
        print(i,j)
col = list()
for i in range(len(prime)):
    col.append("b")
for i in range(sum(prime)):
    col.append("g")
print(*col)