text: #include <stdio.h>
  #include <stdlib.h>
  
  /* Comment/uncomment this to use/disable long_add */
  int long_add(int a, int b, int c, int d);
  
  /* Comment/uncomment this to use/disable extended_add */
  // long extended_add(long a, long b, long c, long d);
  
  int main()
  {
    long a, b, c, d;
    scanf("%ld %ld %ld %ld", &a, &b, &c, &d);
  
    /* Comment/uncomment this to use/disable long_add */
    printf("%d\n", long_add(a, b, c, d));
  
    /* Comment/uncomment this to use/disable extended_add */
    // printf("%ld\n", extended_add(a, b, c, d));
  
    return 0;
  }
  