Problem p02841 (python)

Fixed submission:
from datetime import date

M1,D1=map(int, input().split())
M2,D2=map(int, input().split())

dt1 = date(2019,M1,D1)
dt2 = date(2019,M2,D2)

d = dt2 - dt1
d = d.days

if d != 1:
    print(0)
else:
    if M1 == 1 and D1 == 31:
        print(1)
    elif M1 == 2 and D1 == 28:
        print(1)
    elif M1 == 3 and D1 == 31:
        print(1)
    elif M1 == 4 and D1 == 30:
        print(1)
    elif M1 == 5 and D1 == 31:
        print(1)
    elif M1 == 6 and D1 == 30:
        print(1)
    elif M1 == 7 and D1 == 31:
        print(1)
    elif M1 == 8 and D1 == 31:
        print(1)
    elif M1 == 9 and D1 == 30:
        print(1)
    elif M1 == 10 and D1 == 31:
        print(1)
    elif M1 == 11 and D1 == 30:
        print(1)
    elif M1 == 12 and D1 == 31:
        print(1)
    else:
        print(0)

Buggy submission (verdict: Runtime Error):
M1=int(input())
D1=int(input())
M2=int(input())
D2=int(input())

dt1 = date(2019,M1,D1)
dt2 = date(2019,M2,D2)

d = dt2 - dt1
d = d.days

if d != 1:
    print(0)
else:
    if M1 == 1 and D1 == 31:
        print(1)
    elif M1 == 2 and D1 == 28:
        print(1)
    elif M1 == 3 and D1 == 31:
        print(1)
    elif M1 == 4 and D1 == 30:
        print(1)
    elif M1 == 5 and D1 == 31:
        print(1)
    elif M1 == 6 and D1 == 30:
        print(1)
    elif M1 == 7 and D1 == 31:
        print(1)
    elif M1 == 8 and D1 == 31:
        print(1)
    elif M1 == 9 and D1 == 30:
        print(1)
    elif M1 == 10 and D1 == 31:
        print(1)
    elif M1 == 11 and D1 == 30:
        print(1)
    elif M1 == 12 and D1 == 31:
        print(1)
    else:
        print(0)

Buggy submission (verdict: Runtime Error):
from datetime import date

M1,D1,M2,D2=map(int, input().split())

dt1 = date(2019,M1,D1)
dt2 = date(2019,M2,D2)

d = dt2 - dt1
d = d.days

if d != 1:
    print(0)
else:
    if M1 == 1 and D1 == 31:
        print(1)
    elif M1 == 2 and D1 == 28:
        print(1)
    elif M1 == 3 and D1 == 31:
        print(1)
    elif M1 == 4 and D1 == 30:
        print(1)
    elif M1 == 5 and D1 == 31:
        print(1)
    elif M1 == 6 and D1 == 30:
        print(1)
    elif M1 == 7 and D1 == 31:
        print(1)
    elif M1 == 8 and D1 == 31:
        print(1)
    elif M1 == 9 and D1 == 30:
        print(1)
    elif M1 == 10 and D1 == 31:
        print(1)
    elif M1 == 11 and D1 == 30:
        print(1)
    elif M1 == 12 and D1 == 31:
        print(1)
    else:
        print(0)

Buggy submission (verdict: Runtime Error):
from datetime import date

M1=
M2=
D1=
D2=

dt1 = date(2019,M1,D1)
dt2 = date(2019,M2,D2)

d = dt2 - dt1
d = d.days

if d != 1:
    print(0)
else:
    if M1 == 1 and D1 == 31:
        print(1)
    elif M1 == 2 and D1 == 28:
        print(1)
    elif M1 == 3 and D1 == 31:
        print(1)
    elif M1 == 4 and D1 == 30:
        print(1)
    elif M1 == 5 and D1 == 31:
        print(1)
    elif M1 == 6 and D1 == 30:
        print(1)
    elif M1 == 7 and D1 == 31:
        print(1)
    elif M1 == 8 and D1 == 31:
        print(1)
    elif M1 == 9 and D1 == 30:
        print(1)
    elif M1 == 10 and D1 == 31:
        print(1)
    elif M1 == 11 and D1 == 30:
        print(1)
    elif M1 == 12 and D1 == 31:
        print(1)
    else:
        print(0)