import java.util.Arrays;
import java.util.Scanner;

public class DemoTest4 {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        // 注意 hasNext 和 hasNextLine 的区别
        while (in.hasNextLine()) { // 注意 while 处理多个 case
            int[] arr = Arrays.stream(in.nextLine().split(" ")).mapToInt(Integer::parseInt).toArray();
            System.out.println(solve(arr));
        }
    }
    private static int solve(int[] arr) {
        int min=Integer.MAX_VALUE,res = 0;
        for(int k = -255;k<=255;k++){
            int sum =0;
            for(int i =0;i<arr.length;i++){
                int temp =arr[i]+k;
                if (temp>255) {
                    temp = 255;
                }
                if(temp<0){
                    temp = 0;
                }
                sum+=temp;
            }
            int diff = Math.abs(sum-128*arr.length);
            if(diff<min){
                min =diff;
                res = k;
            }
        }
        return res;
    }
}