import java.util.Scanner;
public class Main {
    public static void main(String[] main){
        Scanner sc = new Scanner(System.in);
        int[] x = new int[5];
        int s = 0;
        for(int i = 0 ; i < 5 ; i++ ){
            x[i] = sc.nextInt();
            if(x[i] == 0){
                s = i + 1;
            }
        }
        System.out.println(s);
        sc.close();
    }
}
/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz