Buggy python submission (verdict: Time Limit Exceeded):
n=int(input())
D=[int(i) for i in input().split()]
if n>=24:
  print(0)
else:
  ans=0
  for i in range(2**(n-1)):
    C=[1]+[0]*23+[1]
    C[D[0]]+=1
    for j in range(n-1):
      if i&(1<<j):
        C[24-D[j+1]]+=1
      else:
        C[D[j+1]]+=1
    cur=24
    if max(C)==1:
      t=0
      for j in range(1,25):
        if C[j]:
          cur=min(cur,t+1)
          t=0
          if not cur:
            break
        else:
          t+=1
    else:
      cur=0
    ans=max(ans,cur)
  print(ans)





Fixed submission:
n=int(input())
D=[int(i) for i in input().split()]
C=[1]+[0]*12

for d in D:
  C[min(d,24-d)]+=1
if max(C)>2 or C[0]>1 or C[12]>1:
  print(0)
else:
  ans=0
  
  for i in range(2**(11)):
    CC=[1]+[0]*23+[1]
    for j in range(1,12):
      if C[j]==2:
        CC[j]=1
        CC[24-j]=1
      elif C[j]==1:
        if i&(1<<(j-1)):
          CC[j]=1
        else:
          CC[24-j]=1
    if C[12]==1:
      CC[12]=1
    cur=24
    t=0
    for j in range(1,25):
      if CC[j]==1:
        cur=min(cur,t+1)
        t=0
      else:
        t+=1
    ans=max(ans,cur)
  print(ans)

Buggy python submission (verdict: Time Limit Exceeded):
n=int(input())
D=[int(i) for i in input().split()]
if n>=24:
  print(0)
else:
  ans=0
  for i in range(2**(n-1)):
    C=[0]*25
    C[0]=1
    C[24]=1
    C[D[0]]+=1
    for j in range(n-1):
      if i&(1<<j):
        C[24-D[j+1]]+=1
      else:
        C[D[j+1]]+=1
    cur=24
    if max(C)==1:
      t=0
      for j in range(1,25):
        if C[j]==1:
          cur=min(cur,t+1)
          t=0
        else:
          t+=1
    else:
      cur=0
    ans=max(ans,cur)
  print(ans)

Fixed submission:
n=int(input())
D=[int(i) for i in input().split()]
C=[1]+[0]*12

for d in D:
  C[min(d,24-d)]+=1
if max(C)>2 or C[0]>1 or C[12]>1:
  print(0)
else:
  ans=0
  
  for i in range(2**(11)):
    CC=[1]+[0]*23+[1]
    for j in range(1,12):
      if C[j]==2:
        CC[j]=1
        CC[24-j]=1
      elif C[j]==1:
        if i&(1<<(j-1)):
          CC[j]=1
        else:
          CC[24-j]=1
    if C[12]==1:
      CC[12]=1
    cur=24
    t=0
    for j in range(1,25):
      if CC[j]==1:
        cur=min(cur,t+1)
        t=0
      else:
        t+=1
    ans=max(ans,cur)
  print(ans)

Buggy python submission (verdict: Time Limit Exceeded):
n=int(input())
D=[int(i) for i in input().split()]
if n>=24:
  print(0)
else:
  ans=0
  for i in range(2**(n-1)):
    C=[0,D[0],24]
    for j in range(n-1):
      if i&(1<<j):
        C.append(24-D[j+1])
      else:
        C.append(D[j+1])
    C.sort()
    cur=24
    for j in range(n+1):
      cur=min(cur,C[j+1]-C[j])
    ans=max(ans,cur)
  print(ans)

Fixed submission:
n=int(input())
D=[int(i) for i in input().split()]
C=[1]+[0]*12

for d in D:
  C[min(d,24-d)]+=1
if max(C)>2 or C[0]>1 or C[12]>1:
  print(0)
else:
  ans=0
  
  for i in range(2**(11)):
    CC=[1]+[0]*23+[1]
    for j in range(1,12):
      if C[j]==2:
        CC[j]=1
        CC[24-j]=1
      elif C[j]==1:
        if i&(1<<(j-1)):
          CC[j]=1
        else:
          CC[24-j]=1
    if C[12]==1:
      CC[12]=1
    cur=24
    t=0
    for j in range(1,25):
      if CC[j]==1:
        cur=min(cur,t+1)
        t=0
      else:
        t+=1
    ans=max(ans,cur)
  print(ans)

Buggy python submission (verdict: Runtime Error):
n=int(input())
D=[int(i) for i in input().split()]
if n>=24:
  print(0)
else:
  ans=0
  for i in range(2**(n-1)):
    C=[0,D[0],24]
    for j in range(n-1):
      if i&(1<<j):
        C.append(24-D[j+1])
      else:
        C.append(D[j+1])
    C.sort()
    cur=24
    for j in range(n):
      cur=min(cur,C[j+1]-C[j])
    ans=max(ans,cur)
print(ans)

Fixed submission:
n=int(input())
D=[int(i) for i in input().split()]
C=[1]+[0]*12

for d in D:
  C[min(d,24-d)]+=1
if max(C)>2 or C[0]>1 or C[12]>1:
  print(0)
else:
  ans=0
  
  for i in range(2**(11)):
    CC=[1]+[0]*23+[1]
    for j in range(1,12):
      if C[j]==2:
        CC[j]=1
        CC[24-j]=1
      elif C[j]==1:
        if i&(1<<(j-1)):
          CC[j]=1
        else:
          CC[24-j]=1
    if C[12]==1:
      CC[12]=1
    cur=24
    t=0
    for j in range(1,25):
      if CC[j]==1:
        cur=min(cur,t+1)
        t=0
      else:
        t+=1
    ans=max(ans,cur)
  print(ans)