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.OutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.FileNotFoundException;
import java.io.File;
import java.util.StringTokenizer;
import java.io.Writer;
import java.io.BufferedReader;
import java.io.FileReader;
import java.io.InputStream;

/**
 * Built using CHelper plug-in
 * Actual solution is at the top
 */
public class Main {
  public static void main(String[] args) {
    InputStream inputStream = System.in;
    OutputStream outputStream = System.out;
    InputReader in = new InputReader(inputStream);
    OutputWriter out = new OutputWriter(outputStream);
    G solver = new G();
    solver.solve(1, in, out);
    out.close();
  }

  static class G extends SimpleSavingChelperSolution {
    public void solve(int testNumber, InputReader in, OutputWriter out) {
      wrapSolve(testNumber, in, out);
    }


    public void solve(int testNumber) {
      int n = in.nextInt();

      int[] a = new int[7];


      int max = 0;

      for (int i = 0; i < n; i++) {
        String s = in.nextString();

        for (int j = 0; j < 7; j++) {
          a[j] += s.charAt(j) == '1' ? 1 : 0;
          max = Math.max(max, a[j]);
        }
      }

      out.println(max);
    }

  }

  static abstract class SimpleSavingChelperSolution extends SavingChelperSolution {

    public String processOutputPreCheck(int testNumber, String output) {
      return output;
    }


    public String processOutputPostCheck(int testNumber, String output) {
      return output;
    }

  }

  static abstract class SavingChelperSolution {
    protected int testNumber;
    public InputReader in;
    public OutputWriter out;
    private OutputWriter toFile;
    private boolean local = new File("chelper.properties").exists();
    public OutputWriter debug;

    {
      if (local) {
        debug = new OutputWriter(System.out);
      } else {
        debug = new OutputWriter(new OutputStream() {

          public void write(int b) {
          }
        });
      }
    }

    public SavingChelperSolution() {
      try {
        toFile = new OutputWriter("last_test_output.txt");
      } catch (FileNotFoundException e) {
        throw new RuntimeException(e);
      }
    }

    public abstract void solve(int testNumber);

    public abstract String processOutputPreCheck(int testNumber, String output);

    public abstract String processOutputPostCheck(int testNumber, String output);

    public void wrapSolve(int testNumber, InputReader in, OutputWriter out) {
      this.testNumber = testNumber;

      ByteArrayOutputStream substituteOutContents = new ByteArrayOutputStream();
      OutputWriter substituteOut = new OutputWriter(substituteOutContents);

      this.in = in;
      this.out = substituteOut;

      solve(testNumber);
      substituteOut.flush();

      String result = substituteOutContents.toString();

      result = processOutputPreCheck(testNumber, result);
      out.print(result);
      out.flush();

      if (local) {
        debug.flush();

        result = processOutputPostCheck(testNumber, result);
        toFile.print(result);
        toFile.flush();
      }
    }

  }

  static class OutputWriter extends PrintWriter {

    public void close() {
      super.close();
    }

    public OutputWriter(String fileName) throws FileNotFoundException {
      super(fileName);
    }

    public OutputWriter(OutputStream outputStream) {
      super(outputStream);
    }

    public OutputWriter(Writer writer) {
      super(writer);
    }

  }

  static class InputReader {
    private BufferedReader br;
    private StringTokenizer in;

    public InputReader(String fileName) {
      try {
        br = new BufferedReader(new FileReader(fileName));
      } catch (IOException e) {
        throw new RuntimeException(e);
      }
    }

    public InputReader(InputStream inputStream) {
      br = new BufferedReader(new InputStreamReader(inputStream));
    }

    private boolean hasMoreTokens() {
      while (in == null || !in.hasMoreTokens()) {
        String s = nextLine();
        if (s == null) {
          return false;
        }
        in = new StringTokenizer(s);
      }
      return true;
    }

    public String nextString() {
      return hasMoreTokens() ? in.nextToken() : null;
    }

    public String nextLine() {
      try {
        in = null;
        return br.readLine();
      } catch (Exception e) {
        e.printStackTrace();
        return null;
      }
    }

    public int nextInt() {
      return Integer.parseInt(nextString());
    }

  }
}

