#include<bits/stdc++.h>
using namespace std;
int main(){
	int i,n=0,b=0,a[20]={0};
	for(i=1;i<=50;i++){
		cin>>b;
		a[b]=a[b]+1;
	}
	for(i=0;i<20;i++){
		if(n<a[i]){
			n=a[i];
		}
	}
	cout<<n;
}

/**************************************************************
	Problem: 1180
	User: chenyaohuo
	Language: C++
	Result: Accepted
	Time:12 ms
	Memory:2072 kb
****************************************************************/