#include<iostream>
#include<algorithm>
#include<cmath>
#include<cstring>
#include<cstdio>
using namespace std;
long long n,a[21],ans=1,d[21],ld=1;
inline int ju(){
    for(int i=1;i<=ld;i++)if(d[i]>=10)return 1;
	return 0;
}
inline void dfs(long long p,long long s){
	if(ju())return;
	if(p==n+1){
		ans=max(ans,s);
		return;
	}
	dfs(p+1,s);
	long long z=0,k=a[p],f=ld;
	while(k)d[++z]+=k%10,k/=10;
	ld=max(ld,z);
	dfs(p+1,s+1);
	ld=f;z=0;k=a[p];
	while(k)d[++z]-=k%10,k/=10;
	return;
}
int main(){
	freopen("cowescape.in","r",stdin);
    freopen("cowescape.out","w",stdout);
	scanf("%lld",&n);
	for(int i=1;i<=n;i++)scanf("%lld",&a[i]);
	dfs(1,0);
	printf("%lld",ans);
	return 0;
}