Problem:
Score : 400 points

Problem Statement

Find the largest integer that can be formed with exactly N matchsticks, under the following conditions:

Every digit in the integer must be one of the digits A_1, A_2, ..., A_M (1 \leq A_i \leq 9).

The number of matchsticks used to form digits 1, 2, 3, 4, 5, 6, 7, 8, 9 should be 2, 5, 5, 4, 5, 6, 3, 7, 6, respectively.

Constraints

All values in input are integers.

2 \leq N \leq 10^4

1 \leq M \leq 9

1 \leq A_i \leq 9

A_i are all different.

There exists an integer that can be formed by exactly N matchsticks under the conditions.

Input

Input is given from Standard Input in the following format:

N M
A_1 A_2 ... A_M

Output

Print the largest integer that can be formed with exactly N matchsticks under the conditions in the problem statement.

Sample Input 1

20 4
3 7 8 4

Sample Output 1

777773

The integer 777773 can be formed with 3 + 3 + 3 + 3 + 3 + 5 = 20 matchsticks, and this is the largest integer that can be formed by 20 matchsticks under the conditions.

Sample Input 2

101 9
9 8 7 6 5 4 3 2 1

Sample Output 2

71111111111111111111111111111111111111111111111111

The output may not fit into a 64-bit integer type.

Sample Input 3

15 3
5 4 6

Sample Output 3

654

Solution in PyPy3 (2.4.0) (judge verdict: Runtime Error)

#!/mnt/c/Users/moiki/bash/env/bin/python
from itertools import permutations
N,M = map(int, input().split())
cost = [0,2,5,5,4,5,6,3,7,6]
A = list(map(int, input().split()))

p = []
for a in A:
    p.append( (cost[a], a) )
costp = sorted(p)


costX = [ z[0] for z in costp]
A = [ z[1] for z in costp]

dp = [""] * (N+1)

for c,a in zip(costX,A):
    i =N 
    dp[i-c] = str(a)

for i in range(N-1, 1, -1):
    if len(dp[i]) == 0:
        continue
    
    for c,a in zip(costX,A):
        for p in permutations( [dp[i], str(a)]):
            if i-c >= 0:
                if dp[i-c] == "":
                    dp[i-c] = str(int( "".join(p)))
                else:
                    dp[i-c] = str(max(int(dp[i-c]), int( "".join(p))))
    
print(dp[0])