using System;
public class Program
{
public static void Main()
int[] a=new int[4];
for(int i=0 ;i<4;i++)
a[i]=Convert.ToInt32(Console.ReadLine());
int max=a[0];
if(max< a[i])
max = a[i];
Console.WriteLine(max);
/* int[] a=new int[4];
for(int i=1;i<4;i++)
if(max<a[i])
max=a[i];
Console.WriteLine(max); */
}