import java.util.*;

public class Main {
	Scanner sc = new Scanner(System.in);
	final int MOD = 998244353;
	final int MAX = Integer.MAX_VALUE;
	final long LMAX = Long.MAX_VALUE;
	int len = (int)1e6 + 1;
	
	
	void doIt() {
		for(int i = 1; i <= 5; i++) {
			if(sc.nextInt() == 0) {
				System.out.println(i);
				return;
			}
		}
	}
	
	
	public static void main(String[] args) {
		new Main().doIt();
	}

}

/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