/* -*- coding: utf-8 -*-
 *
 * 2691.cc:  No.2691 Longest Infection Sequence - yukicoder
 */

#include<cstdio>
#include<algorithm>
 
using namespace std;

/* main */

int main() {
  int a, b, o, w;
  scanf("%d%d%d%d", &a, &b, &o, &w);
  
  printf("%d\n", o + max(a, b) + w);

  return 0;
}