Buggy python submission (verdict: Runtime Error):
n, m = map(int,input().split())

boolins =[]
for i in range(n):
    boolins.append(0)
    
for i in range(m):
    xxx = list(map(int,input().split()))
    if xxx[0] == 1:
        boolins[xxx[1]] = boolins[xxx[1]] + 1
    elif xxx[1] == n :
        boolins[xxx[0]] boolins[xxx[0]]+ 1
    else
        None


if 2 in boolins:
    print('POSSIBLE')
else:
    print('IMPOSSIBLE')

Fixed submission:
n, m = map(int,input().split())

boolins =[]
for i in range(n):
    boolins.append(0)
    
for i in range(m):
    xxx = list(map(int,input().split()))
    if xxx[0] == 1:
        boolins[xxx[1]] = boolins[xxx[1]] + 1
    elif xxx[1] == n :
        boolins[xxx[0]]=boolins[xxx[0]]+ 1
    else:
        None


if 2 in boolins:
    print('POSSIBLE')
else:
    print('IMPOSSIBLE')

Buggy python submission (verdict: Time Limit Exceeded):
n, m = map(int,input().split())
    
aaa = 0
tbin_1 = []
tbin_n = []
for i in range(m):
    xxx = list(map(int,input().split()))
    if xxx[0] == 1:
        tbin_1.append(xxx[1])
        if xxx[1] in tbin_n:
            aaa = 1
            break
            
    elif xxx[1] == n :
        tbin_n.append(xxx[0])
        if xxx[0] in tbin_1:
            aaa = 1
            break
    else:
        None


if aaa == 1 :
    print('POSSIBLE')
else:
    print('IMPOSSIBLE')

Fixed submission:
n, m = map(int,input().split())

boolins =[]
for i in range(n):
    boolins.append(0)
    
for i in range(m):
    xxx = list(map(int,input().split()))
    if xxx[0] == 1:
        boolins[xxx[1]] = boolins[xxx[1]] + 1
    elif xxx[1] == n :
        boolins[xxx[0]]=boolins[xxx[0]]+ 1
    else:
        None


if 2 in boolins:
    print('POSSIBLE')
else:
    print('IMPOSSIBLE')

Buggy python submission (verdict: Time Limit Exceeded):
n, m = map(int,input().split())
    
aaa = 0
tbin_1 = []
tbin_n = []
for i in range(m):
    xxx = list(map(int,input().split()))
    if xxx[0] == 1:
        tbin_1.append(xxx[1])
    elif xxx[1] == n :
        tbin_n.append(xxx[0])
    else:
        None
    if xxx[0] == 1 and xxx[1] in tbin_n:
        aaa = 1
        break
    elif xxx[1] == n and xxx[0] in tbin_1:
        aaa = 1
        break


if aaa == 1 :
    print('POSSIBLE')
else:
    print('IMPOSSIBLE')

Fixed submission:
n, m = map(int,input().split())

boolins =[]
for i in range(n):
    boolins.append(0)
    
for i in range(m):
    xxx = list(map(int,input().split()))
    if xxx[0] == 1:
        boolins[xxx[1]] = boolins[xxx[1]] + 1
    elif xxx[1] == n :
        boolins[xxx[0]]=boolins[xxx[0]]+ 1
    else:
        None


if 2 in boolins:
    print('POSSIBLE')
else:
    print('IMPOSSIBLE')

Buggy python submission (verdict: Time Limit Exceeded):
n, m = map(int,input().split())
    
tbin_o = []

tbin_1 = []
tbin_n = []
for i in range(m):
    xxx = list(map(int,input().split()))
    if xxx[0] == 1:
        tbin_1.append(xxx[1])
    elif xxx[1] == n :
        tbin_n.append(xxx[0])
    else:
        None

aaa = 0
for i in tbin_1:
    if i in tbin_n:
        aaa = 1
        break

if aaa == 1 :
    print('POSSIBLE')
else:
    print('IMPOSSIBLE')

Fixed submission:
n, m = map(int,input().split())

boolins =[]
for i in range(n):
    boolins.append(0)
    
for i in range(m):
    xxx = list(map(int,input().split()))
    if xxx[0] == 1:
        boolins[xxx[1]] = boolins[xxx[1]] + 1
    elif xxx[1] == n :
        boolins[xxx[0]]=boolins[xxx[0]]+ 1
    else:
        None


if 2 in boolins:
    print('POSSIBLE')
else:
    print('IMPOSSIBLE')

Buggy python submission (verdict: Runtime Error):
n, m = map(int,input().split())
    
tbin_o = []

tbin_1 = []
tbin_n = []
for i in range(m):
    xxx = list(map(int,input().split()))
    if xxx[0] == 1:
        tbin_1.append(xxx[1]):
    elif xxx[1] == n :
        tbin_n.append(xxx[0])
    else:
        None

aaa = 0
for i in tbin_1:
    if i in tbin_n:
        aaa = 1
        break

if aaa == 1 :
    print('POSSIBLE')
else:
    print('IMPOSSIBLE')

Fixed submission:
n, m = map(int,input().split())

boolins =[]
for i in range(n):
    boolins.append(0)
    
for i in range(m):
    xxx = list(map(int,input().split()))
    if xxx[0] == 1:
        boolins[xxx[1]] = boolins[xxx[1]] + 1
    elif xxx[1] == n :
        boolins[xxx[0]]=boolins[xxx[0]]+ 1
    else:
        None


if 2 in boolins:
    print('POSSIBLE')
else:
    print('IMPOSSIBLE')

Buggy python submission (verdict: Time Limit Exceeded):
n, m = map(int,input().split())
    
tbin_o = []
for i in range(m):
    xxx = list(map(int,input().split()))
    if xxx[0] == 1 or xxx[1] == n:
        tbin_o.append(xxx)



aaa = 0
for j in range(len(tbin_o)):
    for l in range(len(tbin_o)):
        if tbin_o[j][1] == tbin_o[l][0] and j != l:
            aaa = aaa + 1
            break
            
if aaa == 1 :
    print('POSSIBLE')
else:
    print('IMPOSSIBLE')

Fixed submission:
n, m = map(int,input().split())

boolins =[]
for i in range(n):
    boolins.append(0)
    
for i in range(m):
    xxx = list(map(int,input().split()))
    if xxx[0] == 1:
        boolins[xxx[1]] = boolins[xxx[1]] + 1
    elif xxx[1] == n :
        boolins[xxx[0]]=boolins[xxx[0]]+ 1
    else:
        None


if 2 in boolins:
    print('POSSIBLE')
else:
    print('IMPOSSIBLE')

Buggy python submission (verdict: Time Limit Exceeded):
n, m = map(int,input().split())
    
tbin_o = []
for i in range(m):
    xxx = list(map(int,input().split()))
    tbin_o.append(xxx)

tbin_2 = []
for i in range(len(tbin_o)):
    if tbin_o[i][0] == 1 or tbin_o[i][1] == n:
        tbin_2.append(tbin_o[i])

aaa = 0
for j in range(len(tbin_2)):
    for l in range(len(tbin_2)):
        if tbin_2[j][1] == tbin_2[l][0] and j != l:
            aaa = aaa + 1
            break
            
if aaa == 1 :
    print('POSSIBLE')
else:
    print('IMPOSSIBLE')

Fixed submission:
n, m = map(int,input().split())

boolins =[]
for i in range(n):
    boolins.append(0)
    
for i in range(m):
    xxx = list(map(int,input().split()))
    if xxx[0] == 1:
        boolins[xxx[1]] = boolins[xxx[1]] + 1
    elif xxx[1] == n :
        boolins[xxx[0]]=boolins[xxx[0]]+ 1
    else:
        None


if 2 in boolins:
    print('POSSIBLE')
else:
    print('IMPOSSIBLE')

Buggy python submission (verdict: Runtime Error):
 n, m = map(int,input().split())
    
tbin_o = []
for i in range(m):
    xxx = list(map(int,input().split()))
    tbin_o.append(xxx)

tbin_2 = []
for i in range(len(tbin_o)):
    if tbin_o[i][0] == 1 or tbin_o[i][1] == n:
        tbin_2.append(tbin_o[i])

aaa = 0
for j in range(len(tbin_2)):
    for l in range(len(tbin_2)):
        if tbin_2[j][1] == tbin_2[l][0] and j != l:
            aaa = aaa + 1
            break
            
if aaa == 1 :
    print('POSSIBLE')
else:
    print('IMPOSSIBLE')

Fixed submission:
n, m = map(int,input().split())

boolins =[]
for i in range(n):
    boolins.append(0)
    
for i in range(m):
    xxx = list(map(int,input().split()))
    if xxx[0] == 1:
        boolins[xxx[1]] = boolins[xxx[1]] + 1
    elif xxx[1] == n :
        boolins[xxx[0]]=boolins[xxx[0]]+ 1
    else:
        None


if 2 in boolins:
    print('POSSIBLE')
else:
    print('IMPOSSIBLE')

Buggy python submission (verdict: Runtime Error):
n, m = map(int,input().split())
tbin_o = []
for i in range(m):
    xxx = list(map(int,input().split()))
    tbin.append(xxx)

tbin_2 = []
for i in range(len(tbin_o)):
    if tbin_o[i][0] == 1 or tbin_o[i][i] == n:
        tbin_2.append(tbin_o[i])

aaa = 0
for j in range(len(tbin_2)):
    for l in range(len(tbin_2)):
        if tbin_2[j][1] == tbin_2[l][0] and j != l:
            aaa = aaa + 1
            break
            
if aaa == 1 :
    print('POSSIBLE')
else:
    print('IMPOSSIBLE')

Fixed submission:
n, m = map(int,input().split())

boolins =[]
for i in range(n):
    boolins.append(0)
    
for i in range(m):
    xxx = list(map(int,input().split()))
    if xxx[0] == 1:
        boolins[xxx[1]] = boolins[xxx[1]] + 1
    elif xxx[1] == n :
        boolins[xxx[0]]=boolins[xxx[0]]+ 1
    else:
        None


if 2 in boolins:
    print('POSSIBLE')
else:
    print('IMPOSSIBLE')