import java.util.*;

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

        for(int i=0; i<5; i++){
            if(Integer.parseInt(scan.next()) == 0  ){
                System.out.println(i+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