#define _USE_MATH_DEFINES
#include<stdio.h>
#include<string>
#include<iostream>
#include<cctype>
#include<cstdio>
#include<vector>
#include<stack>
#include<queue>
#include <algorithm>
#include<math.h>
#include<set>
#include<map>
#include<iomanip>

//#include<bits/stdc++.h>



using namespace std;




int main() {

	int a,b,c,d;
	cin>>a>>b>>c>>d;
	int v=max(a,b);
	if((a==b)&&(c==d)&&a>c)v++;
	cout<<v<<endl;
	   
	
	return 0;
}