def f(n):
if n>=1000: return 1000
if n<1000 and n%2==1: return n*f(n+1)
if n<1000 and n%2==0: return n*f(n+1)//2
print(f(998)/f(1001))
def f(n):
if n>=1000: return 1000
if n<1000 and n%2==1: return n*f(n+1)
if n<1000 and n%2==0: return n*f(n+1)//2
print(f(998)/f(1001))
f=[0]*1002
for n in range (1001,0,-1): # значения от 1001 до 1
if n>=1000: f[n]=1000
if n<1000 and n%2==1: f[n]=n*f[n+1]
if n<1000 and n%2==0: f[n]=n*f[n+1]//2
print(f[998]/f[1001])
f=[0]*1002
for n in range (1001,0,-1): # значения от 1001 до 1
if n>=1000: f[n]=1000
if n<1000 and n%2==1: f[n]=n*f[n+1]
if n<1000 and n%2==0: f[n]=n*f[n+1]//2
print(f[998]/f[1001])
