#include<iostream>
#include<iomanip>
#include<math.h>
#include<algorithm> 
#include<cstdio>
#include<cstring>
#include<string>
#include<queue>
#include<vector>
#include<set>
#include<stack>
#include<map>
#define maxn 1000000
using namespace std;
int n,ans=0,idex=0,cnt[1000000];
string  s[maxn];
char tree[maxn][27];
void insert(string s) {
    int p = 0,maxs=0;
    for (int i = 0; s[i]; ++i) {
        int j = s[i] - 'a';
        if (!tree[p][j]) {
            tree[p][j] = ++idex;
        }
        p = tree[p][j];
        maxs += cnt[p];
    }
    cnt[p]++;
    ans = max(maxs+1, ans);
}
int main() {
    cin >> n;
    for (int i = 0; i < n; ++i) {
        cin >> s[i];
        insert(s[i]);
}
    cout << ans;
    return 0;
}

inline int read() {
    int w = 1, q = 0;
    char ch = ' ';
    while (ch != '-' && (ch < '0' || ch > '9')) ch = getchar();
    if (ch == '-') w = -1, ch = getchar();
    while (ch >= '0' && ch <= '9') q = q * 10 + ch - '0', ch = getchar();
    return w * q;
}