#include <bits/stdc++.h>
using namespace std;
#define LL long long
const int MAXN = 2000 + 10;
const int INF = 0x3f3f3f3f;
 
char str[MAXN][80];
 
int dp[MAXN];
 
int main()
{
    //freopen("input.txt", "r", stdin);
    int n, i, j, vmax = -1;
    scanf("%d", &n);
    char *pc;
    for (i = 0; i < n; i++)
        scanf("%s", str[i]);
    for (i = 0; i < n; i++)
        for (j = 0; j < i; j++)
            if ((pc = strstr(str[i], str[j])) != NULL && pc == str[i])
            {
                dp[i] = max(dp[i], dp[j] + 1);
                vmax = max(dp[i], vmax);
            }
    printf("%d\n", vmax + 1);
    return 0;
}