Problem p02922 (python)

Fixed submission:
from math import ceil
A,B = (int(i) for i in input().split())
print(ceil(((B-1)/(A-1))))

Buggy submission (verdict: Runtime Error):
a,b = (int(i) for i in input().split())
if a == 2: 
	 if b == 1:
		ans = 0
	 elif b == 2:
		ans = 1
	 elif b == 3:
		ans = 2
	 elif b == 4:
		ans = 3
	 elif b == 5:
		ans = 4
	 elif b == 6:
		ans = 5
	 elif b == 7:
		ans = 6
	 elif b == 8:
		ans = 7
	 elif b == 9:
		ans = 8
	 elif b == 10:
		ans = 9
	 elif b == 11:
		ans = 10
	 elif b == 12:
		ans = 11
	 elif b == 13:
		ans = 12
	 elif b == 14:
		ans = 13
	 elif b == 15:
		ans = 14
	 elif b == 16:
		ans = 15
	 elif b == 17:
		ans = 16
	 elif b == 18:
		ans = 17
	 elif b == 19:
		ans = 18
	 elif b == 20:
		ans = 19
elif a == 3: 
	 if b == 1:
		ans = 0
	 elif b == 2:
		ans = 1
	 elif b == 3:
		ans = 1
	 elif b == 4:
		ans = 2
	 elif b == 5:
		ans = 2
	 elif b == 6:
		ans = 3
	 elif b == 7:
		ans = 3
	 elif b == 8:
		ans = 4
	 elif b == 9:
		ans = 4
	 elif b == 10:
		ans = 5
	 elif b == 11:
		ans = 5
	 elif b == 12:
		ans = 6
	 elif b == 13:
		ans = 6
	 elif b == 14:
		ans = 7
	 elif b == 15:
		ans = 7
	 elif b == 16:
		ans = 8
	 elif b == 17:
		ans = 8
	 elif b == 18:
		ans = 9
	 elif b == 19:
		ans = 9
	 elif b == 20:
		ans = 10
elif a == 4: 
	 if b == 1:
		ans = 0
	 elif b == 2:
		ans = 1
	 elif b == 3:
		ans = 1
	 elif b == 4:
		ans = 1
	 elif b == 5:
		ans = 2
	 elif b == 6:
		ans = 2
	 elif b == 7:
		ans = 2
	 elif b == 8:
		ans = 3
	 elif b == 9:
		ans = 3
	 elif b == 10:
		ans = 3
	 elif b == 11:
		ans = 4
	 elif b == 12:
		ans = 4
	 elif b == 13:
		ans = 4
	 elif b == 14:
		ans = 5
	 elif b == 15:
		ans = 5
	 elif b == 16:
		ans = 5
	 elif b == 17:
		ans = 6
	 elif b == 18:
		ans = 6
	 elif b == 19:
		ans = 6
	 elif b == 20:
		ans = 7
elif a == 5: 
	 if b == 1:
		ans = 0
	 elif b == 2:
		ans = 1
	 elif b == 3:
		ans = 1
	 elif b == 4:
		ans = 1
	 elif b == 5:
		ans = 1
	 elif b == 6:
		ans = 2
	 elif b == 7:
		ans = 2
	 elif b == 8:
		ans = 2
	 elif b == 9:
		ans = 2
	 elif b == 10:
		ans = 3
	 elif b == 11:
		ans = 3
	 elif b == 12:
		ans = 3
	 elif b == 13:
		ans = 3
	 elif b == 14:
		ans = 4
	 elif b == 15:
		ans = 4
	 elif b == 16:
		ans = 4
	 elif b == 17:
		ans = 4
	 elif b == 18:
		ans = 5
	 elif b == 19:
		ans = 5
	 elif b == 20:
		ans = 5
elif a == 6: 
	 if b == 1:
		ans = 0
	 elif b == 2:
		ans = 1
	 elif b == 3:
		ans = 1
	 elif b == 4:
		ans = 1
	 elif b == 5:
		ans = 1
	 elif b == 6:
		ans = 1
	 elif b == 7:
		ans = 2
	 elif b == 8:
		ans = 2
	 elif b == 9:
		ans = 2
	 elif b == 10:
		ans = 2
	 elif b == 11:
		ans = 2
	 elif b == 12:
		ans = 3
	 elif b == 13:
		ans = 3
	 elif b == 14:
		ans = 3
	 elif b == 15:
		ans = 3
	 elif b == 16:
		ans = 3
	 elif b == 17:
		ans = 4
	 elif b == 18:
		ans = 4
	 elif b == 19:
		ans = 4
	 elif b == 20:
		ans = 4
elif a == 7: 
	 if b == 1:
		ans = 0
	 elif b == 2:
		ans = 1
	 elif b == 3:
		ans = 1
	 elif b == 4:
		ans = 1
	 elif b == 5:
		ans = 1
	 elif b == 6:
		ans = 1
	 elif b == 7:
		ans = 1
	 elif b == 8:
		ans = 2
	 elif b == 9:
		ans = 2
	 elif b == 10:
		ans = 2
	 elif b == 11:
		ans = 2
	 elif b == 12:
		ans = 2
	 elif b == 13:
		ans = 2
	 elif b == 14:
		ans = 3
	 elif b == 15:
		ans = 3
	 elif b == 16:
		ans = 3
	 elif b == 17:
		ans = 3
	 elif b == 18:
		ans = 3
	 elif b == 19:
		ans = 3
	 elif b == 20:
		ans = 4
elif a == 8: 
	 if b == 1:
		ans = 0
	 elif b == 2:
		ans = 1
	 elif b == 3:
		ans = 1
	 elif b == 4:
		ans = 1
	 elif b == 5:
		ans = 1
	 elif b == 6:
		ans = 1
	 elif b == 7:
		ans = 1
	 elif b == 8:
		ans = 1
	 elif b == 9:
		ans = 2
	 elif b == 10:
		ans = 2
	 elif b == 11:
		ans = 2
	 elif b == 12:
		ans = 2
	 elif b == 13:
		ans = 2
	 elif b == 14:
		ans = 2
	 elif b == 15:
		ans = 2
	 elif b == 16:
		ans = 3
	 elif b == 17:
		ans = 3
	 elif b == 18:
		ans = 3
	 elif b == 19:
		ans = 3
	 elif b == 20:
		ans = 3
elif a == 9: 
	 if b == 1:
		ans = 0
	 elif b == 2:
		ans = 1
	 elif b == 3:
		ans = 1
	 elif b == 4:
		ans = 1
	 elif b == 5:
		ans = 1
	 elif b == 6:
		ans = 1
	 elif b == 7:
		ans = 1
	 elif b == 8:
		ans = 1
	 elif b == 9:
		ans = 1
	 elif b == 10:
		ans = 2
	 elif b == 11:
		ans = 2
	 elif b == 12:
		ans = 2
	 elif b == 13:
		ans = 2
	 elif b == 14:
		ans = 2
	 elif b == 15:
		ans = 2
	 elif b == 16:
		ans = 2
	 elif b == 17:
		ans = 2
	 elif b == 18:
		ans = 3
	 elif b == 19:
		ans = 3
	 elif b == 20:
		ans = 3
elif a == 10: 
	 if b == 1:
		ans = 0
	 elif b == 2:
		ans = 1
	 elif b == 3:
		ans = 1
	 elif b == 4:
		ans = 1
	 elif b == 5:
		ans = 1
	 elif b == 6:
		ans = 1
	 elif b == 7:
		ans = 1
	 elif b == 8:
		ans = 1
	 elif b == 9:
		ans = 1
	 elif b == 10:
		ans = 1
	 elif b == 11:
		ans = 2
	 elif b == 12:
		ans = 2
	 elif b == 13:
		ans = 2
	 elif b == 14:
		ans = 2
	 elif b == 15:
		ans = 2
	 elif b == 16:
		ans = 2
	 elif b == 17:
		ans = 2
	 elif b == 18:
		ans = 2
	 elif b == 19:
		ans = 2
	 elif b == 20:
		ans = 3
elif a == 11: 
	 if b == 1:
		ans = 0
	 elif b == 2:
		ans = 1
	 elif b == 3:
		ans = 1
	 elif b == 4:
		ans = 1
	 elif b == 5:
		ans = 1
	 elif b == 6:
		ans = 1
	 elif b == 7:
		ans = 1
	 elif b == 8:
		ans = 1
	 elif b == 9:
		ans = 1
	 elif b == 10:
		ans = 1
	 elif b == 11:
		ans = 1
	 elif b == 12:
		ans = 2
	 elif b == 13:
		ans = 2
	 elif b == 14:
		ans = 2
	 elif b == 15:
		ans = 2
	 elif b == 16:
		ans = 2
	 elif b == 17:
		ans = 2
	 elif b == 18:
		ans = 2
	 elif b == 19:
		ans = 2
	 elif b == 20:
		ans = 2
elif a == 12: 
	 if b == 1:
		ans = 0
	 elif b == 2:
		ans = 1
	 elif b == 3:
		ans = 1
	 elif b == 4:
		ans = 1
	 elif b == 5:
		ans = 1
	 elif b == 6:
		ans = 1
	 elif b == 7:
		ans = 1
	 elif b == 8:
		ans = 1
	 elif b == 9:
		ans = 1
	 elif b == 10:
		ans = 1
	 elif b == 11:
		ans = 1
	 elif b == 12:
		ans = 1
	 elif b == 13:
		ans = 2
	 elif b == 14:
		ans = 2
	 elif b == 15:
		ans = 2
	 elif b == 16:
		ans = 2
	 elif b == 17:
		ans = 2
	 elif b == 18:
		ans = 2
	 elif b == 19:
		ans = 2
	 elif b == 20:
		ans = 2
elif a == 13: 
	 if b == 1:
		ans = 0
	 elif b == 2:
		ans = 1
	 elif b == 3:
		ans = 1
	 elif b == 4:
		ans = 1
	 elif b == 5:
		ans = 1
	 elif b == 6:
		ans = 1
	 elif b == 7:
		ans = 1
	 elif b == 8:
		ans = 1
	 elif b == 9:
		ans = 1
	 elif b == 10:
		ans = 1
	 elif b == 11:
		ans = 1
	 elif b == 12:
		ans = 1
	 elif b == 13:
		ans = 1
	 elif b == 14:
		ans = 2
	 elif b == 15:
		ans = 2
	 elif b == 16:
		ans = 2
	 elif b == 17:
		ans = 2
	 elif b == 18:
		ans = 2
	 elif b == 19:
		ans = 2
	 elif b == 20:
		ans = 2
elif a == 14: 
	 if b == 1:
		ans = 0
	 elif b == 2:
		ans = 1
	 elif b == 3:
		ans = 1
	 elif b == 4:
		ans = 1
	 elif b == 5:
		ans = 1
	 elif b == 6:
		ans = 1
	 elif b == 7:
		ans = 1
	 elif b == 8:
		ans = 1
	 elif b == 9:
		ans = 1
	 elif b == 10:
		ans = 1
	 elif b == 11:
		ans = 1
	 elif b == 12:
		ans = 1
	 elif b == 13:
		ans = 1
	 elif b == 14:
		ans = 1
	 elif b == 15:
		ans = 2
	 elif b == 16:
		ans = 2
	 elif b == 17:
		ans = 2
	 elif b == 18:
		ans = 2
	 elif b == 19:
		ans = 2
	 elif b == 20:
		ans = 2
elif a == 15: 
	 if b == 1:
		ans = 0
	 elif b == 2:
		ans = 1
	 elif b == 3:
		ans = 1
	 elif b == 4:
		ans = 1
	 elif b == 5:
		ans = 1
	 elif b == 6:
		ans = 1
	 elif b == 7:
		ans = 1
	 elif b == 8:
		ans = 1
	 elif b == 9:
		ans = 1
	 elif b == 10:
		ans = 1
	 elif b == 11:
		ans = 1
	 elif b == 12:
		ans = 1
	 elif b == 13:
		ans = 1
	 elif b == 14:
		ans = 1
	 elif b == 15:
		ans = 1
	 elif b == 16:
		ans = 2
	 elif b == 17:
		ans = 2
	 elif b == 18:
		ans = 2
	 elif b == 19:
		ans = 2
	 elif b == 20:
		ans = 2
elif a == 16: 
	 if b == 1:
		ans = 0
	 elif b == 2:
		ans = 1
	 elif b == 3:
		ans = 1
	 elif b == 4:
		ans = 1
	 elif b == 5:
		ans = 1
	 elif b == 6:
		ans = 1
	 elif b == 7:
		ans = 1
	 elif b == 8:
		ans = 1
	 elif b == 9:
		ans = 1
	 elif b == 10:
		ans = 1
	 elif b == 11:
		ans = 1
	 elif b == 12:
		ans = 1
	 elif b == 13:
		ans = 1
	 elif b == 14:
		ans = 1
	 elif b == 15:
		ans = 1
	 elif b == 16:
		ans = 1
	 elif b == 17:
		ans = 2
	 elif b == 18:
		ans = 2
	 elif b == 19:
		ans = 2
	 elif b == 20:
		ans = 2
elif a == 17: 
	 if b == 1:
		ans = 0
	 elif b == 2:
		ans = 1
	 elif b == 3:
		ans = 1
	 elif b == 4:
		ans = 1
	 elif b == 5:
		ans = 1
	 elif b == 6:
		ans = 1
	 elif b == 7:
		ans = 1
	 elif b == 8:
		ans = 1
	 elif b == 9:
		ans = 1
	 elif b == 10:
		ans = 1
	 elif b == 11:
		ans = 1
	 elif b == 12:
		ans = 1
	 elif b == 13:
		ans = 1
	 elif b == 14:
		ans = 1
	 elif b == 15:
		ans = 1
	 elif b == 16:
		ans = 1
	 elif b == 17:
		ans = 1
	 elif b == 18:
		ans = 2
	 elif b == 19:
		ans = 2
	 elif b == 20:
		ans = 2
elif a == 18: 
	 if b == 1:
		ans = 0
	 elif b == 2:
		ans = 1
	 elif b == 3:
		ans = 1
	 elif b == 4:
		ans = 1
	 elif b == 5:
		ans = 1
	 elif b == 6:
		ans = 1
	 elif b == 7:
		ans = 1
	 elif b == 8:
		ans = 1
	 elif b == 9:
		ans = 1
	 elif b == 10:
		ans = 1
	 elif b == 11:
		ans = 1
	 elif b == 12:
		ans = 1
	 elif b == 13:
		ans = 1
	 elif b == 14:
		ans = 1
	 elif b == 15:
		ans = 1
	 elif b == 16:
		ans = 1
	 elif b == 17:
		ans = 1
	 elif b == 18:
		ans = 1
	 elif b == 19:
		ans = 2
	 elif b == 20:
		ans = 2
elif a == 19: 
	 if b == 1:
		ans = 0
	 elif b == 2:
		ans = 1
	 elif b == 3:
		ans = 1
	 elif b == 4:
		ans = 1
	 elif b == 5:
		ans = 1
	 elif b == 6:
		ans = 1
	 elif b == 7:
		ans = 1
	 elif b == 8:
		ans = 1
	 elif b == 9:
		ans = 1
	 elif b == 10:
		ans = 1
	 elif b == 11:
		ans = 1
	 elif b == 12:
		ans = 1
	 elif b == 13:
		ans = 1
	 elif b == 14:
		ans = 1
	 elif b == 15:
		ans = 1
	 elif b == 16:
		ans = 1
	 elif b == 17:
		ans = 1
	 elif b == 18:
		ans = 1
	 elif b == 19:
		ans = 1
	 elif b == 20:
		ans = 2
elif a == 20: 
	 if b == 1:
		ans = 0
	 elif b == 2:
		ans = 1
	 elif b == 3:
		ans = 1
	 elif b == 4:
		ans = 1
	 elif b == 5:
		ans = 1
	 elif b == 6:
		ans = 1
	 elif b == 7:
		ans = 1
	 elif b == 8:
		ans = 1
	 elif b == 9:
		ans = 1
	 elif b == 10:
		ans = 1
	 elif b == 11:
		ans = 1
	 elif b == 12:
		ans = 1
	 elif b == 13:
		ans = 1
	 elif b == 14:
		ans = 1
	 elif b == 15:
		ans = 1
	 elif b == 16:
		ans = 1
	 elif b == 17:
		ans = 1
	 elif b == 18:
		ans = 1
	 elif b == 19:
		ans = 1
	 elif b == 20:
		ans = 1
print(ans)