Problem p03680 (python)

Fixed submission:
N=int(input())
lamps=[]
for a in range(N):
    _=int(input())
    lamps.append(_)
lamps.insert(0,"aaa")

PressedButtons=[False]*int(N+1)

a=1
count=0

if lamps.count(2)==0:
    print("-1")
    exit()

while PressedButtons[a]==False :
    PressedButtons[a]=True
    count+=1
    a=lamps[a]
    if a==2:
        print(count)
        exit()
print('-1')

Buggy submission (verdict: Runtime Error):
N=int(input())
lamps=[]
for a in range(N):
    _=int(input())
    lamps.append(_)
lamps.insert(0,"aaa")

PressedButtons=[False]*N

a=1
count=0

if lamps.count(2)==0:
    print("-1")
    exit()

while PressedButtons[a]==False :
    PressedButtons[a]=True
    count+=1
    a=lamps[a]
    if a==2:
        print(count)
        exit()
print('-1')

Buggy submission (verdict: Runtime Error):
N=int(input())
lamps=[]
for a in range(N):
    _=int(input())
    lamps.append(_)
lamps.insert(0,"aaa")

PressedButtons=[False]*N

a=1
count=0

if lamps.count(2)==0:
    print("-1")

while PressedButtons[a]==False :
    PressedButtons[a]=True
    count+=1
    a=lamps[a]
    if a==2:
        print(count)
        exit()
print('-1')

Buggy submission (verdict: Runtime Error):
N=int(input())
lamps=[]
for a in range(N):
    _=int(input())
    lamps.append(_)
lamps.insert(0,"aaa")

PressedButtons=[False]*N

a=1
count=0

while PressedButtons[a]==False :
    PressedButtons[a]=True
    count+=1
    a=lamps[a]
    if a==2:
        print(count)
        exit()
print('-1')

Buggy submission (verdict: Runtime Error):
N=int(input())
lamps=[]
for a in range(N):
    _=int(input())
    lamps.append(_)
lamps.insert(0,"aaa")

PressedButtons=[False]*N

a=1
count=0

while True:
    if PressedButtons[a]==False:
        PressedButtons[a]=True
        count+=1
        a=lamps[a]
        if a==2:
            print(count)
            exit()
    # elif PressedButtons[a]==True:
    #     print("-1")
    #     exit()
    # else:
    #     print("-1")
    #     exit()
print("-1")

Buggy submission (verdict: Runtime Error):
N=int(input())
lamps=[]
for a in range(N):
    _=int(input())
    lamps.append(_)
lamps.insert(0,"aaa")

PressedButtons=[False]*N

a=1
count=0


while True:
    if PressedButtons[a]==False:
        PressedButtons[a]=True
        count+=1
        a=lamps[a]
        if a==2:
            print(count)
            exit()
    elif PressedButtons[a]==True:
        print("-1")
        exit()
    else:
        print("-1")
        exit()
print("-1")

Buggy submission (verdict: Runtime Error):
N=int(input())
lamps=[]
for a in range(N):
    _=int(input())
    lamps.append(_)
lamps.insert(0,"aaa")

PressedButtons=[False]*N

a=1
count=0


while True:
    if PressedButtons[a]==False:
        PressedButtons[a]=True
        count+=1
        a=lamps[a]
        if a==2:
            print(count)
            exit()
    elif PressedButtons[a]==True:
        print("-1")
        exit()
    else:
        print("-1")
        exit()

Buggy submission (verdict: Runtime Error):
N=int(input())
lamps=[]
for a in range(N):
    _=int(input())
    lamps.append(_)
lamps.insert(0,"aaa")

PressedButtons=[False]*N

a=1
count=0


while True:
    if PressedButtons[a]==False:
        PressedButtons[a]=True
        count+=1
        a=lamps[a]
        if a==2:
            print(count)
            exit()
    elif PressedButtons[a]==True:
        print("-1")
        exit()
    else:
        print("-1")

Buggy submission (verdict: Runtime Error):
N=int(input())
lamps=[]
for a in range(N):
    _=int(input())
    lamps.append(_)
lamps.insert(0,"aaa")

PressedButtons=[False]*N

a=1
count=0

while True:
    if PressedButtons[a]==False:
        PressedButtons[a]=True
        count+=1
        a=lamps[a]
        if a==2:
            print(count)
    elif PressedButtons[a]==True:
        print("-1")
        exit()
    else:
        print("-1")

Buggy submission (verdict: Runtime Error):
N=int(input())
lamps=[]
for a in range(N):
    _=int(input())
    lamps.append(_)
lamps.insert(0,-1)

if lamps.count(2)==0:
    print("-1")
    exit()

# no2=[i for i , x in enumerate(lamps) if x==2]
PressedButton=[]

num=2
while lamps[1]!=num:
    a=lamps.index(num)
    if PressedButton.count(a)==0:
        PressedButton.append(a)
        num=a
    else:
        print("-1")
        exit()
print(PressedButton)

Buggy submission (verdict: Runtime Error):
N=int(input())
lamps=[]
for a in range(N):
    _=int(input())
    lamps.append(_)

if lamps.count(2)==0:
    print("-1")
    exit()

# no2=[i for i , x in enumerate(lamps) if x==2]
PressedButton=[]

num=2
while lamps[0]!=num:
    a=lamps.index(num)
    if PressedButton.count(a)==0:
        PressedButton.append(a)
        num=a
    else:
        print("-1")
        exit()
print(PressedButton)