#include<bits/stdc++.h>
using namespace std;
int main()
{
	int n,m=0,i;
	int a[20]={};
	for(i=0;i<50;i++){
		cin>>n;
		a[n]++;
	} 
	for(i=0;i<20;i++){
		if(a[i]>m){
			m=a[i];
		}
	}
	cout<<m;
	return 0;
}

/**************************************************************
	Problem: 1180
	User: zzz
	Language: C++
	Result: Accepted
	Time:8 ms
	Memory:2072 kb
****************************************************************/