Drazil is playing a math game with Varda.

Let's define <image> for positive integer x as a product of factorials of its digits. For example, <image>.

First, they choose a decimal number a consisting of n digits that contains at least one digit larger than 1. This number may possibly start with leading zeroes. Then they should find maximum positive number x satisfying following two conditions:

1. x doesn't contain neither digit 0 nor digit 1.

2. <image> = <image>.

Help friends find such number.

Input

The first line contains an integer n (1 ≤ n ≤ 15) — the number of digits in a.

The second line contains n digits of a. There is at least one digit in a that is larger than 1. Number a may possibly contain leading zeroes.

Output

Output a maximum possible integer satisfying the conditions above. There should be no zeroes and ones in this number decimal representation.

Examples

Input

4
1234


Output

33222


Input

3
555


Output

555

Note

In the first case, <image>
n = input()
F_a = input()
mass_1 = []
mass_2 = []
mas = []
for i in F_a:
    mass_1.append(int(i))

for i in mass_1:
    if i == 2:
       mas = [2]
       if len(mass_2) > 0:
            for j in mas:
                flag = True
                for y in range(len(mass_2)):
                    if j >= mass_2[y]:
                        mass_2.insert(y, j)
                        flag = False
                        break
                if flag:
                    mass_2.append(j)

       else:
           mass_2.append(2)
    elif i == 3:
        mas = [3]
        if len(mass_2) > 0:
            for j in mas:
                flag = True
                for y in range(len(mass_2)):
                    if j >= mass_2[y]:
                        mass_2.insert(y, j)
                        flag = False
                        break
                if flag:
                    mass_2.append(j)

        else:
            mass_2.append(3)
    elif i == 4:
        mas = [3, 2, 2]
        if len(mass_2) > 0:
            for j in mas:
                flag = True
                for y in range(len(mass_2)):
                    if j >= mass_2[y]:
                        mass_2.insert(y, j)
                        flag = False
                        break
                if flag:
                    mass_2.append(j)

        else:
            mass_2.append(3)
            mass_2.append(2)
            mass_2.append(2)
    elif i == 5:
        mas = [5]
        if len(mass_2) > 0:
            for j in mas:
                flag = True
                for y in range(len(mass_2)):
                    if j >= mass_2[y]:
                        mass_2.insert(y, j)
                        flag = False
                        break
                if flag:
                    mass_2.append(j)

        else:
            mass_2.append(5)
    elif i == 6:
        mas = [5, 3]
        if len(mass_2) > 0:
            for j in mas:
                flag = True
                for y in range(len(mass_2)):
                    if j >= mass_2[y]:
                        mass_2.insert(y, j)
                        flag = False
                        break
                if flag:
                    mass_2.append(j)

        else:
            mass_2.append(5)
            mass_2.append(3)
    elif i == 7:
        mas = [7]
        if len(mass_2) > 0:
            for j in mas:
                flag = True
                for y in range(len(mass_2)):
                    if j >= mass_2[y]:
                        mass_2.insert(y, j)
                        flag = False
                        break
                if flag:
                    mass_2.append(j)

        else:
            mass_2.append(7)
    elif i == 8:
        mas = [7, 2, 2, 2]
        if len(mass_2) > 0:
            for j in mas:
                flag = True
                for y in range(len(mass_2)):
                    if j >= mass_2[y]:
                        mass_2.insert(y, j)
                        flag = False
                        break
                if flag:
                    mass_2.append(j)

        else:
            mass_2.append(7)
            mass_2.append(2)
            mass_2.append(2)
            mass_2.append(2)
    elif i == 9:
        mas = [7, 3, 3, 2]
        if len(mass_2) > 0:
            for j in mas:
                flag = True
                for y in range(len(mass_2)):
                    if j >= mass_2[y]:
                        mass_2.insert(y, j)
                        flag = False
                        break
                if flag:
                    mass_2.append(j)
        else:
            mass_2.append(7)
            mass_2.append(3)
            mass_2.append(3)
            mass_2.append(2)
a = ''
for i in mass_2:
    a = a + str(i)
print(a)