Buggy python submission (verdict: Runtime Error):
N, M = map(int, input().split())
A = [int(a) for a in input().split()]
if 1 in A:
    if 4 in A: A.remove(4)
    if 6 in A: A.remove(6)
    if 9 in A: A.remove(9)
if 3 in A:
    if 2 in A: A.remove(2)
if 5 in A:
    if 3 in A: A.remove(3)
    if 2 in A: A.remove(2)
if 7 in A:
    if 6 in A: A.remove(6)
    if 9 in A: A.remove(9)
if 9 in A:
    if 6 in A: A.remove(6)

def MatchNum(i):
    if i == 1: return 2
    elif i == 4: return 4
    elif i in [2, 3, 5]: return 5
    elif i == 7: return 3
    elif i == 8: return 7
    elif i in [6, 9]: return 6

MatchUse = []
for a in A:
    MatchUse.append((a, MatchNum(a)))

DP = [-1] * (N+1)
for a, num in MatchUse:
    DP[num] = a

for i in range(2, N):
    if DP[i] > 0:
        temp = DP[i]*10
        for a, num in MatchUse:
            if i + num <= N:
                DP[i + num] = max(DP[i + num], a + temp)
print(DP[N])

Fixed submission:
N, M = map(int, input().split())
A = [int(a) for a in input().split()]
if 1 in A:
    if 4 in A: A.remove(4)
    if 6 in A: A.remove(6)
    if 9 in A: A.remove(9)
if 3 in A:
    if 2 in A: A.remove(2)
if 5 in A:
    if 3 in A: A.remove(3)
    if 2 in A: A.remove(2)
if 7 in A:
    if 6 in A: A.remove(6)
    if 9 in A: A.remove(9)
if 9 in A:
    if 6 in A: A.remove(6)

def MatchNum(i):
    if i == 1: return 2
    elif i == 4: return 4
    elif i in [2, 3, 5]: return 5
    elif i == 7: return 3
    elif i == 8: return 7
    elif i in [6, 9]: return 6

MatchUse = []
for a in A:
    MatchUse.append((a, MatchNum(a)))

DP = [-1] * (N+1)
for a, num in MatchUse:
    if num <= N: DP[num] = a

for i in range(2, N):
    if DP[i] > 0:
        temp = DP[i]*10
        for a, num in MatchUse:
            if i + num <= N:
                DP[i + num] = max(DP[i + num], a + temp)
print(DP[N])

Buggy python submission (verdict: Runtime Error):
N, M = map(int, input().split())
A = [int(a) for a in input().split()]
if 1 in A:
    if 4 in A: A.remove(4)
    if 6 in A: A.remove(6)
    if 9 in A: A.remove(9)
if 3 in A:
    if 2 in A: A.remove(2)
if 5 in A:
    if 3 in A: A.remove(3)
    if 2 in A: A.remove(2)
if 7 in A:
    if 6 in A: A.remove(6)
    if 9 in A: A.remove(9)
if 9 in A:
    if 6 in A: A.remove(6)

def MatchNum(i):
    if i == 1: return 2
    elif i == 4: return 4
    elif i in [2, 3, 5]: return 5
    elif i == 7: return 3
    elif i == 8: return 7
    elif i in [6, 9]: return 6

DP = [""] * (N+1)
for key in A:
    DP[MatchNum(key)] = str(key)

for i in range(1, N):
    if DP[i]:
        for key in A:
            if i + MatchNum(key) <= N:
                if not DP[i + MatchNum(key)]:  DP[i + MatchNum(key)] = str(key) + DP[i] 
                elif int(DP[i + MatchNum(key)]) < int(str(key) + DP[i]):
                    DP[i + MatchNum(key)] = str(key) + DP[i]
print(DP[N])


Fixed submission:
N, M = map(int, input().split())
A = [int(a) for a in input().split()]
if 1 in A:
    if 4 in A: A.remove(4)
    if 6 in A: A.remove(6)
    if 9 in A: A.remove(9)
if 3 in A:
    if 2 in A: A.remove(2)
if 5 in A:
    if 3 in A: A.remove(3)
    if 2 in A: A.remove(2)
if 7 in A:
    if 6 in A: A.remove(6)
    if 9 in A: A.remove(9)
if 9 in A:
    if 6 in A: A.remove(6)

def MatchNum(i):
    if i == 1: return 2
    elif i == 4: return 4
    elif i in [2, 3, 5]: return 5
    elif i == 7: return 3
    elif i == 8: return 7
    elif i in [6, 9]: return 6

MatchUse = []
for a in A:
    MatchUse.append((a, MatchNum(a)))

DP = [-1] * (N+1)
for a, num in MatchUse:
    if num <= N: DP[num] = a

for i in range(2, N):
    if DP[i] > 0:
        temp = DP[i]*10
        for a, num in MatchUse:
            if i + num <= N:
                DP[i + num] = max(DP[i + num], a + temp)
print(DP[N])