package com.codegym.task.task05.task0532;
import java.io.*;
/*
Task about algorithms
*/
public class Solution {
public static void main(String[] args) throws Exception {
BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
int max=0;
int b = 0;
//write your code here
while (true) {
int a = Integer.parseInt(reader.readLine());
if (a > 0) {
if (a >= b) max= a;
else max = b;
}
b = a;
}
System.out.println(max);
}
}