import java.util.Scanner;

public class Main {
  public static void main(String[] args) {

    Scanner sc = new Scanner(System.in);

    String[] a = sc.nextLine().split(" ");
    
    int[] nums = new int[a.length];
    
    for(int i=0; i<nums.length; i++) {
      nums[i] = Integer.parseInt(a[i]);
    }
    
    for(int i = 0; i<nums.length; i++) {
      if (nums[i] == 0) {
        System.out.println(i+1);
        break;
      }
    }
    
    


  }
}
/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