import java.util.Scanner;

public class Main{
  public static void main(String[]args){
    int pos=-1;
    Scanner sc=new Scanner(System.in);
    int[] a=new int[5];
    for(int i=0;i<5;i++){
      a[i]=sc.nextInt();
      if(a[i]==0)
        pos=i;
    }
    System.out.println(pos+1);
  }
}

/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