i was solving this problem in python 3.6

https://www.codechef.com/problems/VACCINE2

I used my own scenarios too and i got the correct solution according to the question but still I am getting an error for some reason i dont know why please help

this is my code

import math

t=int(input())

for p in range(t):

n = list(map(int, input().split()))

l = list(map(int, input().split()))

D = n[1]

R = []

NR = []

for i in l:

if i>=80 or i<=9:

R.append(i)

else:

NR.append(i)

x=len®

z=len(NR)

if x/D==0:

x=1

else:

x=math.ceil(x/D)

if z/D==0:

z=1

else:

z=math.ceil(z/D)

`print(z+x)`