#include <iostream>
#include <cstdio>
#include <cmath>
#include <cstring>
#include <string>
using namespace std;
int weight[25];
int n,A,ans=0,rd[25];
void init()
{
	scanf("%d",&n);
	for(int i=1;i<=n;i++)
		scanf("%d",&weight[i]);
}
void check()
{
	int nums[11];
	memset(nums,0,sizeof(nums));
	for(int i=1;i<=A;i++)
	{
		int cnt=1;
		int tmp=weight[rd[i]];
		while(tmp!=0)
		{
			nums[cnt]+=tmp%10;
			tmp/=10;
			cnt++;
		}
	}
	for(int i=1;i<=10;i++)
	{
		if(nums[i]>=10)
			return ;
	}
	if(A>ans)
		ans=A;
}
void dfs(int num)
{
	if(num==n+1)
	{
		check();
		return ;
	}
	rd[++A]=num;
	dfs(num+1);
	A--;
	dfs(num+1);
}
int main()
{
	freopen("cowescape.in","r",stdin);
	freopen("cowescape.out","w",stdout);
	init();
	dfs(1);
	printf("%d",ans);
	return 0;
}