There are n student groups at the university. During the study day, each group can take no more than 7 classes. Seven time slots numbered from 1 to 7 are allocated for the classes.

The schedule on Monday is known for each group, i. e. time slots when group will have classes are known.

Your task is to determine the minimum number of rooms needed to hold classes for all groups on Monday. Note that one room can hold at most one group class in a single time slot.

Input

The first line contains a single integer n (1 ≤ n ≤ 1000) — the number of groups. 

Each of the following n lines contains a sequence consisting of 7 zeroes and ones — the schedule of classes on Monday for a group. If the symbol in a position equals to 1 then the group has class in the corresponding time slot. In the other case, the group has no class in the corresponding time slot.

Output

Print minimum number of rooms needed to hold all groups classes on Monday.

Examples

Input

2
0101010
1010101


Output

1


Input

3
0101011
0011001
0110111


Output

3

Note

In the first example one room is enough. It will be occupied in each of the seven time slot by the first group or by the second group.

In the second example three rooms is enough, because in the seventh time slot all three groups have classes.
import java.io.*;
import java.util.Arrays;
import java.util.StringTokenizer;

public class Solution {


    static MyScanner sc;
    private static PrintWriter out;
    static long M = 1000000007;


    public static void main(String[] s) throws Exception {
        StringBuilder stringBuilder = new StringBuilder();
//
//        stringBuilder.append("200000 200000 ");
//        Random x = new Random(3);
//
//        for (int i = 0; i < 400000; i++) {
//            stringBuilder.append(x.nextInt() + " ");
//        }


        if (stringBuilder.length() == 0) {
            sc = new MyScanner(System.in);
        } else {
            sc = new MyScanner(new BufferedReader(new StringReader(stringBuilder.toString())));
        }

        out = new PrintWriter(new OutputStreamWriter(System.out));

        initData();
        solve();
        out.flush();
    }


    private static void initData() {
    }

    private static void solve() throws IOException {
        long n = sc.fi();

        int [] t = new int[7];
        for (int i = 0 ; i < n ; i++) {
            String k = sc.next();
            for (int l = 0 ; l < 7 ; l++) {
                if (k.charAt(l) == '1') t[l]++;
            }
        }
        out.println(Arrays.stream(t).max().getAsInt());
    }


    private static void solveT() throws IOException {
        int t = sc.nextInt();
        while (t-- > 0) {
            solve();
        }
    }


    private static long gcd(long l, long l1) {
        if (l > l1) return gcd(l1, l);
        if (l == 0) return l1;
        return gcd(l1 % l, l);
    }

    private static long pow(long a, long b, long m) {
        if (b == 0) return 1;
        if (b == 1) return a;
        long pp = pow(a, b / 2, m);
        pp *= pp;
        pp %= m;
        return (pp * (b % 2 == 0 ? 1 : a)) % m;
    }


    static class MyScanner {
        BufferedReader br;
        StringTokenizer st;

        MyScanner(BufferedReader br) {
            this.br = br;
        }

        public MyScanner(InputStream in) {
            this(new BufferedReader(new InputStreamReader(in)));
        }

        void findToken() {
            while (st == null || !st.hasMoreTokens()) {
                try {
                    st = new StringTokenizer(br.readLine());
                } catch (IOException e) {
                    throw new RuntimeException(e);
                }
            }
        }

        String next() {
            findToken();
            return st.nextToken();
        }

        Integer[] nab(int n) {
            Integer[] k = new Integer[n];
            for (int i = 0; i < n; i++) {
                k[i] = sc.fi();
            }
            return k;
        }

        int[] na(int n) {
            int[] k = new int[n];
            for (int i = 0; i < n; i++) {
                k[i] = sc.fi();
            }
            return k;
        }

        long[] nl(int n) {
            long[] k = new long[n];
            for (int i = 0; i < n; i++) {
                k[i] = sc.nextLong();
            }
            return k;
        }

        int nextInt() {
            return Integer.parseInt(next());
        }

        int fi() {
            String t = next();
            int cur = 0;
            boolean n = t.charAt(0) == '-';
            for (int a = n ? 1 : 0; a < t.length(); a++) {
                cur = cur * 10 + t.charAt(a) - '0';
            }
            return n ? -cur : cur;
        }

        long nextLong() {
            return Long.parseLong(next());
        }

        double nextDouble() {
            return Double.parseDouble(next());
        }
    }

}