228A.cpp

//DEFINITE

using namespace std;
#include <iostream>
#include <string>
#include <math.h>
#include <stdio.h>
#include <bits/stdc++.h>
#define mem(x,val) memset((x),(val),sizeof(x));
#define rite(x) freopen(x,"w",stdout);
#define read(x) freopen(x,"r",stdin);
#define all(x) x.begin(),x.end()
#define sz(x) ((int)x.size())
#define pb push_back
#define clr clear()
#define FASTINPUT       ios_base::sync_with_stdio(0);cin.tie(0);
typedef long long int lli;
typedef unsigned long long int ulli;
typedef vector<int> vi;
typedef map<int,int> mii;
typedef set<int> si;
typedef pair<int,int> pii;
typedef vector<pii> vpii;

int main()
{
    FASTINPUT
    set<int>s;
    int n=4;
    int count=0;
    while(n--)
    {
    	int t;
    	cin>>t;
    	if(s.find(t)!=s.end())count+=1;
    	s.insert(t);
    }
    cout<<count<<endl;


    return 0;
}