import java.util.Scanner;
public class Beaya10
{

static Scanner in = new Scanner(System.in);
public static void main()
{
int n = 0;
int c = 0;
int a = 0;
int b = 0;
System.out.println("Please insert a number and press enter");
n = in.nextInt();
b = n;
while (n!=0)
{
c++;
n = n/10;
}
//System.out.println(c);
int[] x = new int[c];
while (a != c)
{
x[a] = b%10;
b = b/10;
System.out.println("x["+a+"] = " + x[a]);
a++;
}
a = 0;
int max;
int min;
while (a<c);
{
max = Math.max(x[a],x[a+1]);
a++;
}
System.out.println(max);
}
}