X = int(input())
if X == 1:
    print(2)
    print(1,2)
    print('b g')
    exit()
res = []
x = 2
while x < 2*10**5:
    if X%x != 0:
        x += 1
        continue
    while X%x == 0:
        X //= x
        res.append(x)
    x += 1
if X >= 2:
    print(-1)
    exit()
n = len(res)
for i in range(len(res)):
    n += res[i]
if n > 2*10**5:
    print(-1)
    exit()
E = []
C = ['g' for _ in range(n)]
for i in range(len(res)):
    C[i] = 'b'
for i in range(len(res)-1):
    E.append((i+1,i+2))
idx = len(res)
for i in range(len(res)):
    for j in range(res[i]):
        E.append((i+1,idx+1))
        idx += 1
print(n)
for u,v in E:
    print(u,v)
print(*C)