#include<bits/stdc++.h>
using namespace std;
#define ll long long
ll n,m,k,x;
int main()
{
	scanf("%d",&n);
	for(int i=1;i<=n;i++){
		scanf("%d",&m);
		k=0;
		while(m){
			k+=m%10;
			m/=10;
		}
		x=max(k,x);
	}	
	printf("%d",x);
	return 0;
}