TwoSideSums

import java.util.Scanner;
public class TheSUm {
    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);

        String[] line = scan.nextLine().split(" ");
        int[] arr = new int[line.length];
        for(int a = 0; a < arr.length; a ++) {
            arr[a] = Integer.parseInt(line[a]);
        }

            for(int i =0; i < arr.length; i++) {
                int leftSum = 0;
                int rightSum = 0;
                for (int l = 0; l < i; l++) {
                    leftSum += arr[l];
                }
                for (int r = 0; r < arr.length; r++) {
                    rightSum += arr[r];
                }
                if (leftSum == rightSum) {
                    System.out.print(i);
                    break;
                }
            }
            System.out.print("no");

            }
        }