蒟蒻刚学OI 本地AC提交RE 求大佬指教

from math import *

n = int(input())
a = 0
b = 1

for i in range(1,n+1):
    b*=i
for i in range(1,n+1):
    a+=(b//i)
a*=n
c = gcd(a,b)
a = a//c
b = b//c
d = a//b
a = a%b

if(a == 0):
    print(d)
else:
    w = int(log10(d)+1)
    for i in range(w):
        print(" ",end='')
    print(a)
    print(d,end='')
    w=int(log10(b)+1)
    for i in range(w):
        print("-",end='')
    print()
    w = int(log10(d)+1)
    for i in range(w):
        print(" ",end='')
    print(b)