n=int(input())
a=[]
while n%4==0:
	a.append(4)
	n//=4
while n%6==0:
	a.append(6)
	n//=6
for i in range(2,200000):
	while n%i==0:
		a.append(i)
		n//=i
if sum(a)+len(a)>=200000 or n!=1:
	print(-1)
elif n==1 and len(a)==0:
  print("""2
1 2
b g""")
else:
	print(sum(a)+len(a))
	nt=0
	for i in range(len(a)):
		for j in range(a[i]):
			print(i+1,len(a)+nt+1)
			nt+=1
	print(*["b"]*len(a),*["g"]*sum(a))