CF 554B Ohana Cleans Up

B. Ohana Cleans Up

time limit per test

2 seconds

memory limit per test

256 megabytes

input

standard input

output

standard output

Ohana Matsumae is trying to clean a room, which is divided up into an n by n grid of squares. Each square is initially either clean or dirty. Ohana can sweep her broom over columns of the grid. Her broom is very strange: if she sweeps over a clean square, it will become dirty, and if she sweeps over a dirty square, it will become clean. She wants to sweep some columns of the room to maximize the number of rows that are completely clean. It is not allowed to sweep over the part of the column, Ohana can only sweep the whole column.

Return the maximum number of rows that she can make completely clean.

Input

The first line of input will be a single integer n (1 ≤ n ≤ 100).

The next n lines will describe the state of the room. The i-th line will contain a binary string with n characters denoting the state of the i-th row of the room. The j-th character on this line is '1' if the j-th square in the i-th row is clean, and '0' if it is dirty.

Output

The output should be a single line containing an integer equal to a maximum possible number of rows that are completely clean.

Sample test(s)

input

40101100011110101

output

2

input

3111111111

output

3

Note

In the first sample, Ohana can sweep the 1st and 3rd columns. This will make the 1st and 4th row be completely clean.

In the second sample, everything is already clean, so Ohana doesn't need to do anything.

这个人要打扫卫生，她是一列一列来打扫的，但是他的扫把很奇怪，干净的地抹过之后变脏，脏的地相反。

求她最多能使多少行变成干净的。

这是个技巧题，只要两行的字符串相等，这两行她就能做到同时使他们变干净，否则不成立。

可以举几个例子自己验证。

#include<iostream>#include<cstdio>#include<map>#include<cstring>#include<string>using namespace std;map<string,int> mp ;int main(){int n;cin >> n;int ans = 0;for(int i=0;i<n;i++){string s;cin >> s;ans = max(ans,++mp[s]);}cout<<ans<<endl;return 0;}