import java.util.Arrays;
import java.util.StringTokenizer;

public class Test.java{
    public static int[] Add(int[] originalArr, int val){
        int[] newArray = Arrays.copy0f(originalArr, originalArr.length+1);
        newArray[newArray.length-1] = val;
        return newArray;
    }

    public static void main(String[] args) {
        String tast1 = "15,-41,12,42,-12,2,4";
        String tast2 = tast1.replaceAll("[^0-9,-]",",");
        StringTokenizer strtoken = new StringTokenizer(tast2,",");
        int[] originalArr = new int[strtoken.countTokens()];
        int index = 0;

        while(strtoken.hasMoreTokens()){
            originalArr[index] = Integer.parseInt(strtoken.nextToken());
            index++;
        }
        int[] newArray = Add(originalArr,99);
        int maxNumber = Integer.MIN_VALUE;

        for(int number : newArray){
            if(number>maxNumber){
                maxNumber = number;
            }
        }

        System.out.print(maxNumber);
        
    }
}