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

/**************************************************************
	Problem: 1180
	User: chenjunlin
	Language: C++
	Result: Accepted
	Time:9 ms
	Memory:2072 kb
****************************************************************/