#include<bits/stdc++.h>
using namespace std;
int main()
{
    int a[55];
    int c[25] = {0};
    for(int i=0;i<50;i++)
    {
        cin>>a[i];
        c[a[i]] = c[a[i]] + 1;
    }
    int m=0;
    for(int i=0;i<20;i++)
    {
        if(c[i] > m)
        {
            m = c[i];
        }
    }
    cout<<m;
    return 0;
}
/**************************************************************
	Problem: 1180
	User: wuyichen
	Language: C++
	Result: Accepted
	Time:14 ms
	Memory:2072 kb
****************************************************************/