package com.codegym.task.task05.task0532;

import java.util.Scanner;

/*
Task about algorithms

*/

public class Solution {
    public static void main(String[] args) throws Exception {
       Scanner input = new Scanner(System.in);
        int maximum = Integer.MIN_VALUE;

        while(input.hasNextLine()){
            int N = Integer.parseInt(input.nextLine());
            if(N > 0 && N > maximum){
                maximum = N;
            }

        }

        if(maximum > 0){
            System.out.println(maximum);
        } else {
            //display nothing
        }


   }
}