class Node:
    def __init__(self,id):
        
        self.id=id
    def __lt__(self,other):
        if str(self.id)+str(other.id)<str(other.id)+str(self.id):
            return True
            
n=int(input())
s=list(map(int,input().split()))
ling_num=s.count(0)
s=[item for item in s if item>0]

alist=list()
for item in s:
    alist.append(Node(item))

alist.sort()
print(alist[0].id,end="")
print("0"*ling_num,end="")
for i in range(1,len(alist)):
    print(alist[i].id,end="")





/**************************************************************
	Problem: 1452
	User: admin
	Language: Python
	Result: Accepted
	Time:192 ms
	Memory:34480 kb
****************************************************************/