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 Python (3.4.3) (judge verdict: Wrong Answer)

arr = [0,2,5,5,4,5,6,3,7,6]
N,M = map(int,input().split())
src = sorted(list(map(int,input().split())),key = lambda x:arr[x])
dim = 0
num = 0
min_num = src[0]
for i in src:
    tmp = 1 + (N-arr[i])//arr[min_num]
    if dim <= tmp and num < i:
        dim = tmp
        num = i
s = str(num)
cnt = N - arr[num]
cnt_dim = 1
while(cnt_dim + 1 < dim):
    s += str(min_num)
    cnt -= arr[min_num]
    cnt_dim += 1
for i in src:
    if cnt == arr[i]:
        if i <= min_num:
            s += str(i)
            break
        else:
            s = s[:1] + str(i) + s[1:]
            break
print(s)