X = int(input())

n_div = [0]*(X+1)

for i in range(1,X//2+1):
    for j in range(i, X+1, i):
        n_div[j] += 1
    
d = {}
for a in range(1, X//2+1):
    b = X-a
    f = abs((a-n_div[a])-(b-n_div[b]))
    if f not in d:
        d[f] = [[a, b]]
    else:
        d[f].append([a, b])

ans = sorted(d[min(d.keys())])
for v in ans:
    a, b = v
    print(a, b)
    
for v in ans[::-1]:
    a, b = v
    if a != b:
        print(b, a)