def factorization(n):
    arr = []
    temp = n
    i=2
    while i*i<=n:
        if temp%i==0:
            cnt=0
            while temp%i==0:
                cnt+=1
                temp //= i
            arr.append([i, cnt])
        i+=1
    if temp!=1:
        arr.append([temp, 1])
    return arr

edge=[]
color=["b"]
big = 0
X=int(input())
fac=factorization(X)
if len(fac)==0:
    fac.append((1,1))
left=0
for a,b in fac:
    for _ in range(b):
        big+=1
        if big!=1:
            edge.append((left,big))
            color.append("b")
        if big>2*10**5:
            print(-1)
            exit(0)
        left=big
        for i in range(a):
            big+=1
            edge.append((left,big))
            color.append("g")
            if big>2*10**5:
                print(-1)
                exit(0)
print(big)
for u,v in edge:
    print(u, v)
print(*color)