import java.util.*;
import java.io.*;
import java.math.*;
/*
javac Main.java
java Main > a.txt
*/
public class Main
{  
    
    public static void process()throws IOException
    {
     for(int i=0;i<5;i++)
       {
        long x=nl();
        if(x==0)
        {
            pn(i+1);break;
        }
       }
   
    }
    static AnotherReader sc;
    static PrintWriter out;
    public static void main(String[]args)throws IOException
    {
        out = new PrintWriter(System.out);
        sc=new AnotherReader();
        boolean oj = true;
         //PrintWriter out=new PrintWriter("output");
        //oj = System.getProperty("ONLINE_JUDGE") != null;
        //if(!oj) sc=new AnotherReader(100);
      
         //int T=ni(); while(T-->0)
            process();
           
      
        long s = System.currentTimeMillis();
      
        out.flush();
        if(!oj)
            System.out.println(System.currentTimeMillis()-s+"ms");
        System.out.close();  
    }
    static void sort(long arr[],int n)
    {
    shuffle(arr,n);
    Arrays.sort(arr);
    }
    static void shuffle(long arr[],int n)
    {
        Random r=new Random();
        for(int i=0;i<n;i++)
        {
          long temp=arr[i];
          int pos=i+r.nextInt(n-i);
          arr[i]=arr[pos];
          arr[pos]=temp;
        }
    }
 
    static void pn(Object o){out.println(o);}
    static void p(Object o){out.print(o);}
    static void pni(Object o){out.println(o);System.out.flush();}
    static int ni()throws IOException{return sc.nextInt();}
    static long nl()throws IOException{return sc.nextLong();}
    static double nd()throws IOException{return sc.nextDouble();}
    static String nln()throws IOException{return sc.nextLine();}
    static String nn()throws IOException{return sc.next();}
    static long gcd(long a, long b)throws IOException{return (b==0)?a:gcd(b,a%b);}
    static int gcd(int a, int b)throws IOException{return (b==0)?a:gcd(b,a%b);}
    static int bit(long n)throws IOException{return (n==0)?0:(1+bit(n&(n-1)));}
    static int[] iarr(int N)throws IOException{int[]ARR=new int[N];for(int i=0;i<N;i++){ARR[i]=ni();}return ARR;}
    static long[] larr(int N)throws IOException{long[]ARR=new long[N];for(int i=0;i<N;i++){ARR[i]=nl();}return ARR;}
    static boolean multipleTC=false;
 
/////////////////////////////////////////////////////////////////////////////////////////////////////////
    static class AnotherReader{BufferedReader br; StringTokenizer st;
    AnotherReader()throws FileNotFoundException{
    br=new BufferedReader(new InputStreamReader(System.in));}
    AnotherReader(int a)throws FileNotFoundException{
    br = new BufferedReader(new FileReader("input.txt"));}
    String next()throws IOException{
    while (st == null || !st.hasMoreElements()) {try{
    st = new StringTokenizer(br.readLine());}
    catch (IOException  e){ e.printStackTrace(); }}
    return st.nextToken(); } int nextInt() throws IOException{
    return Integer.parseInt(next());}
    long nextLong() throws IOException
    {return Long.parseLong(next());}
    double nextDouble()throws IOException { return Double.parseDouble(next()); }
    String nextLine() throws IOException{ String str = ""; try{
    str = br.readLine();} catch (IOException e){
    e.printStackTrace();} return str;}}
    
/////////////////////////////////////////////////////////////////////////////////////////////////////////////
}
    
     import java.util.*; util.* java import java.io.*; io.* java import java.math.*; math.* java public class Main
{  
    
    public static void process()throws IOException
    {
     for(int i=0;i<5;i++)
       {
        long x=nl();
        if(x==0)
        {
            pn(i+1);break;
        }
       }
   
    }
    static AnotherReader sc;
    static PrintWriter out;
    public static void main(String[]args)throws IOException
    {
        out = new PrintWriter(System.out);
        sc=new AnotherReader();
        boolean oj = true;
         //PrintWriter out=new PrintWriter("output");
        //oj = System.getProperty("ONLINE_JUDGE") != null;
        //if(!oj) sc=new AnotherReader(100);
      
         //int T=ni(); while(T-->0)
            process();
           
      
        long s = System.currentTimeMillis();
      
        out.flush();
        if(!oj)
            System.out.println(System.currentTimeMillis()-s+"ms");
        System.out.close();  
    }
    static void sort(long arr[],int n)
    {
    shuffle(arr,n);
    Arrays.sort(arr);
    }
    static void shuffle(long arr[],int n)
    {
        Random r=new Random();
        for(int i=0;i<n;i++)
        {
          long temp=arr[i];
          int pos=i+r.nextInt(n-i);
          arr[i]=arr[pos];
          arr[pos]=temp;
        }
    }
 
    static void pn(Object o){out.println(o);}
    static void p(Object o){out.print(o);}
    static void pni(Object o){out.println(o);System.out.flush();}
    static int ni()throws IOException{return sc.nextInt();}
    static long nl()throws IOException{return sc.nextLong();}
    static double nd()throws IOException{return sc.nextDouble();}
    static String nln()throws IOException{return sc.nextLine();}
    static String nn()throws IOException{return sc.next();}
    static long gcd(long a, long b)throws IOException{return (b==0)?a:gcd(b,a%b);}
    static int gcd(int a, int b)throws IOException{return (b==0)?a:gcd(b,a%b);}
    static int bit(long n)throws IOException{return (n==0)?0:(1+bit(n&(n-1)));}
    static int[] iarr(int N)throws IOException{int[]ARR=new int[N];for(int i=0;i<N;i++){ARR[i]=ni();}return ARR;}
    static long[] larr(int N)throws IOException{long[]ARR=new long[N];for(int i=0;i<N;i++){ARR[i]=nl();}return ARR;}
    static boolean multipleTC=false;
 
/////////////////////////////////////////////////////////////////////////////////////////////////////////
    static class AnotherReader{BufferedReader br; StringTokenizer st;
    AnotherReader()throws FileNotFoundException{
    br=new BufferedReader(new InputStreamReader(System.in));}
    AnotherReader(int a)throws FileNotFoundException{
    br = new BufferedReader(new FileReader("input.txt"));}
    String next()throws IOException{
    while (st == null || !st.hasMoreElements()) {try{
    st = new StringTokenizer(br.readLine());}
    catch (IOException  e){ e.printStackTrace(); }}
    return st.nextToken(); } int nextInt() throws IOException{
    return Integer.parseInt(next());}
    long nextLong() throws IOException
    {return Long.parseLong(next());}
    double nextDouble()throws IOException { return Double.parseDouble(next()); }
    String nextLine() throws IOException{ String str = ""; try{
    str = br.readLine();} catch (IOException e){
    e.printStackTrace();} return str;}}
    
/////////////////////////////////////////////////////////////////////////////////////////////////////////////
} Main static AnotherReader sc; sc static PrintWriter out; out static boolean multipleTC=false; multipleTC false public static void process()throws IOException
    {
     for(int i=0;i<5;i++)
       {
        long x=nl();
        if(x==0)
        {
            pn(i+1);break;
        }
       }
   
    } process {
     for(int i=0;i<5;i++)
       {
        long x=nl();
        if(x==0)
        {
            pn(i+1);break;
        }
       }
   
    } for(int i=0;i<5;i++)
       {
        long x=nl();
        if(x==0)
        {
            pn(i+1);break;
        }
       } int i=0; int i=0; i 0 i<5 i 5 i++ i++ i {
        long x=nl();
        if(x==0)
        {
            pn(i+1);break;
        }
       } {
        long x=nl();
        if(x==0)
        {
            pn(i+1);break;
        }
       } long x=nl(); x nl() nl if(x==0)
        {
            pn(i+1);break;
        } x==0 x 0 {
            pn(i+1);break;
        } pn(i+1) pn i+1 i 1 break; public static void main(String[]args)throws IOException
    {
        out = new PrintWriter(System.out);
        sc=new AnotherReader();
        boolean oj = true;
         //PrintWriter out=new PrintWriter("output");
        //oj = System.getProperty("ONLINE_JUDGE") != null;
        //if(!oj) sc=new AnotherReader(100);
      
         //int T=ni(); while(T-->0)
            process();
           
      
        long s = System.currentTimeMillis();
      
        out.flush();
        if(!oj)
            System.out.println(System.currentTimeMillis()-s+"ms");
        System.out.close();  
    } main {
        out = new PrintWriter(System.out);
        sc=new AnotherReader();
        boolean oj = true;
         //PrintWriter out=new PrintWriter("output");
        //oj = System.getProperty("ONLINE_JUDGE") != null;
        //if(!oj) sc=new AnotherReader(100);
      
         //int T=ni(); while(T-->0)
            process();
           
      
        long s = System.currentTimeMillis();
      
        out.flush();
        if(!oj)
            System.out.println(System.currentTimeMillis()-s+"ms");
        System.out.close();  
    } out = new PrintWriter(System.out) out new PrintWriter(System.out) sc=new AnotherReader() sc new AnotherReader() boolean oj = true; oj true process() process long s = System.currentTimeMillis(); s System.currentTimeMillis() System.currentTimeMillis System out.flush() out.flush out if(!oj)
            System.out.println(System.currentTimeMillis()-s+"ms"); !oj oj System.out.println(System.currentTimeMillis()-s+"ms") System.out.println System.out System System.out System.currentTimeMillis()-s+"ms" System.currentTimeMillis()-s System.currentTimeMillis() System.currentTimeMillis System s "ms" System.out.close() System.out.close System.out System System.out String[]args args static void sort(long arr[],int n)
    {
    shuffle(arr,n);
    Arrays.sort(arr);
    } sort {
    shuffle(arr,n);
    Arrays.sort(arr);
    } shuffle(arr,n) shuffle arr n Arrays.sort(arr) Arrays.sort Arrays arr long arr[] arr int n n static void shuffle(long arr[],int n)
    {
        Random r=new Random();
        for(int i=0;i<n;i++)
        {
          long temp=arr[i];
          int pos=i+r.nextInt(n-i);
          arr[i]=arr[pos];
          arr[pos]=temp;
        }
    } shuffle {
        Random r=new Random();
        for(int i=0;i<n;i++)
        {
          long temp=arr[i];
          int pos=i+r.nextInt(n-i);
          arr[i]=arr[pos];
          arr[pos]=temp;
        }
    } Random r=new Random(); r new Random() for(int i=0;i<n;i++)
        {
          long temp=arr[i];
          int pos=i+r.nextInt(n-i);
          arr[i]=arr[pos];
          arr[pos]=temp;
        } int i=0; int i=0; i 0 i<n i n i++ i++ i {
          long temp=arr[i];
          int pos=i+r.nextInt(n-i);
          arr[i]=arr[pos];
          arr[pos]=temp;
        } {
          long temp=arr[i];
          int pos=i+r.nextInt(n-i);
          arr[i]=arr[pos];
          arr[pos]=temp;
        } long temp=arr[i]; temp arr[i] arr i int pos=i+r.nextInt(n-i); pos i+r.nextInt(n-i) i r.nextInt(n-i) r.nextInt r n-i n i arr[i]=arr[pos] arr[i] arr i arr[pos] arr pos arr[pos]=temp arr[pos] arr pos temp long arr[] arr int n n static void pn(Object o){out.println(o);} pn {out.println(o);} out.println(o) out.println out o Object o o static void p(Object o){out.print(o);} p {out.print(o);} out.print(o) out.print out o Object o o static void pni(Object o){out.println(o);System.out.flush();} pni {out.println(o);System.out.flush();} out.println(o) out.println out o System.out.flush() System.out.flush System.out System System.out Object o o static int ni()throws IOException{return sc.nextInt();} ni {return sc.nextInt();} return sc.nextInt(); sc.nextInt() sc.nextInt sc static long nl()throws IOException{return sc.nextLong();} nl {return sc.nextLong();} return sc.nextLong(); sc.nextLong() sc.nextLong sc static double nd()throws IOException{return sc.nextDouble();} nd {return sc.nextDouble();} return sc.nextDouble(); sc.nextDouble() sc.nextDouble sc static String nln()throws IOException{return sc.nextLine();} nln {return sc.nextLine();} return sc.nextLine(); sc.nextLine() sc.nextLine sc static String nn()throws IOException{return sc.next();} nn {return sc.next();} return sc.next(); sc.next() sc.next sc static long gcd(long a, long b)throws IOException{return (b==0)?a:gcd(b,a%b);} gcd {return (b==0)?a:gcd(b,a%b);} return (b==0)?a:gcd(b,a%b); (b==0)?a:gcd(b,a%b) (b==0) b 0 a gcd(b,a%b) gcd b a%b a b long a a long b b static int gcd(int a, int b)throws IOException{return (b==0)?a:gcd(b,a%b);} gcd {return (b==0)?a:gcd(b,a%b);} return (b==0)?a:gcd(b,a%b); (b==0)?a:gcd(b,a%b) (b==0) b 0 a gcd(b,a%b) gcd b a%b a b int a a int b b static int bit(long n)throws IOException{return (n==0)?0:(1+bit(n&(n-1)));} bit {return (n==0)?0:(1+bit(n&(n-1)));} return (n==0)?0:(1+bit(n&(n-1))); (n==0)?0:(1+bit(n&(n-1))) (n==0) n 0 0 (1+bit(n&(n-1))) 1 bit(n&(n-1)) bit n&(n-1) n (n-1) n 1 long n n static int[] iarr(int N)throws IOException{int[]ARR=new int[N];for(int i=0;i<N;i++){ARR[i]=ni();}return ARR;} iarr {int[]ARR=new int[N];for(int i=0;i<N;i++){ARR[i]=ni();}return ARR;} int[]ARR=new int[N]; ARR new int[N] N for(int i=0;i<N;i++){ARR[i]=ni();} int i=0; int i=0; i 0 i<N i N i++ i++ i {ARR[i]=ni();} {ARR[i]=ni();} ARR[i]=ni() ARR[i] ARR i ni() ni return ARR; ARR int N N static long[] larr(int N)throws IOException{long[]ARR=new long[N];for(int i=0;i<N;i++){ARR[i]=nl();}return ARR;} larr {long[]ARR=new long[N];for(int i=0;i<N;i++){ARR[i]=nl();}return ARR;} long[]ARR=new long[N]; ARR new long[N] N for(int i=0;i<N;i++){ARR[i]=nl();} int i=0; int i=0; i 0 i<N i N i++ i++ i {ARR[i]=nl();} {ARR[i]=nl();} ARR[i]=nl() ARR[i] ARR i nl() nl return ARR; ARR int N N     static class AnotherReader{BufferedReader br; StringTokenizer st;
    AnotherReader()throws FileNotFoundException{
    br=new BufferedReader(new InputStreamReader(System.in));}
    AnotherReader(int a)throws FileNotFoundException{
    br = new BufferedReader(new FileReader("input.txt"));}
    String next()throws IOException{
    while (st == null || !st.hasMoreElements()) {try{
    st = new StringTokenizer(br.readLine());}
    catch (IOException  e){ e.printStackTrace(); }}
    return st.nextToken(); } int nextInt() throws IOException{
    return Integer.parseInt(next());}
    long nextLong() throws IOException
    {return Long.parseLong(next());}
    double nextDouble()throws IOException { return Double.parseDouble(next()); }
    String nextLine() throws IOException{ String str = ""; try{
    str = br.readLine();} catch (IOException e){
    e.printStackTrace();} return str;}} AnotherReader BufferedReader br; br StringTokenizer st; st AnotherReader()throws FileNotFoundException{
    br=new BufferedReader(new InputStreamReader(System.in));} AnotherReader {
    br=new BufferedReader(new InputStreamReader(System.in));} br=new BufferedReader(new InputStreamReader(System.in)) br new BufferedReader(new InputStreamReader(System.in)) AnotherReader(int a)throws FileNotFoundException{
    br = new BufferedReader(new FileReader("input.txt"));} AnotherReader {
    br = new BufferedReader(new FileReader("input.txt"));} br = new BufferedReader(new FileReader("input.txt")) br new BufferedReader(new FileReader("input.txt")) int a a String next()throws IOException{
    while (st == null || !st.hasMoreElements()) {try{
    st = new StringTokenizer(br.readLine());}
    catch (IOException  e){ e.printStackTrace(); }}
    return st.nextToken(); } next {
    while (st == null || !st.hasMoreElements()) {try{
    st = new StringTokenizer(br.readLine());}
    catch (IOException  e){ e.printStackTrace(); }}
    return st.nextToken(); } while (st == null || !st.hasMoreElements()) {try{
    st = new StringTokenizer(br.readLine());}
    catch (IOException  e){ e.printStackTrace(); }} st == null || !st.hasMoreElements() st == null st null !st.hasMoreElements() st.hasMoreElements() st.hasMoreElements st {try{
    st = new StringTokenizer(br.readLine());}
    catch (IOException  e){ e.printStackTrace(); }} try{
    st = new StringTokenizer(br.readLine());}
    catch (IOException  e){ e.printStackTrace(); } catch (IOException  e){ e.printStackTrace(); } IOException  e { e.printStackTrace(); } e.printStackTrace() e.printStackTrace e {
    st = new StringTokenizer(br.readLine());} st = new StringTokenizer(br.readLine()) st new StringTokenizer(br.readLine()) return st.nextToken(); st.nextToken() st.nextToken st int nextInt() throws IOException{
    return Integer.parseInt(next());} nextInt {
    return Integer.parseInt(next());} return Integer.parseInt(next()); Integer.parseInt(next()) Integer.parseInt Integer next() next long nextLong() throws IOException
    {return Long.parseLong(next());} nextLong {return Long.parseLong(next());} return Long.parseLong(next()); Long.parseLong(next()) Long.parseLong Long next() next double nextDouble()throws IOException { return Double.parseDouble(next()); } nextDouble { return Double.parseDouble(next()); } return Double.parseDouble(next()); Double.parseDouble(next()) Double.parseDouble Double next() next String nextLine() throws IOException{ String str = ""; try{
    str = br.readLine();} catch (IOException e){
    e.printStackTrace();} return str;} nextLine { String str = ""; try{
    str = br.readLine();} catch (IOException e){
    e.printStackTrace();} return str;} String str = ""; str "" try{
    str = br.readLine();} catch (IOException e){
    e.printStackTrace();} catch (IOException e){
    e.printStackTrace();} IOException e {
    e.printStackTrace();} e.printStackTrace() e.printStackTrace e {
    str = br.readLine();} str = br.readLine() str br.readLine() br.readLine br return str; str public class Main
{  
    
    public static void process()throws IOException
    {
     for(int i=0;i<5;i++)
       {
        long x=nl();
        if(x==0)
        {
            pn(i+1);break;
        }
       }
   
    }
    static AnotherReader sc;
    static PrintWriter out;
    public static void main(String[]args)throws IOException
    {
        out = new PrintWriter(System.out);
        sc=new AnotherReader();
        boolean oj = true;
         //PrintWriter out=new PrintWriter("output");
        //oj = System.getProperty("ONLINE_JUDGE") != null;
        //if(!oj) sc=new AnotherReader(100);
      
         //int T=ni(); while(T-->0)
            process();
           
      
        long s = System.currentTimeMillis();
      
        out.flush();
        if(!oj)
            System.out.println(System.currentTimeMillis()-s+"ms");
        System.out.close();  
    }
    static void sort(long arr[],int n)
    {
    shuffle(arr,n);
    Arrays.sort(arr);
    }
    static void shuffle(long arr[],int n)
    {
        Random r=new Random();
        for(int i=0;i<n;i++)
        {
          long temp=arr[i];
          int pos=i+r.nextInt(n-i);
          arr[i]=arr[pos];
          arr[pos]=temp;
        }
    }
 
    static void pn(Object o){out.println(o);}
    static void p(Object o){out.print(o);}
    static void pni(Object o){out.println(o);System.out.flush();}
    static int ni()throws IOException{return sc.nextInt();}
    static long nl()throws IOException{return sc.nextLong();}
    static double nd()throws IOException{return sc.nextDouble();}
    static String nln()throws IOException{return sc.nextLine();}
    static String nn()throws IOException{return sc.next();}
    static long gcd(long a, long b)throws IOException{return (b==0)?a:gcd(b,a%b);}
    static int gcd(int a, int b)throws IOException{return (b==0)?a:gcd(b,a%b);}
    static int bit(long n)throws IOException{return (n==0)?0:(1+bit(n&(n-1)));}
    static int[] iarr(int N)throws IOException{int[]ARR=new int[N];for(int i=0;i<N;i++){ARR[i]=ni();}return ARR;}
    static long[] larr(int N)throws IOException{long[]ARR=new long[N];for(int i=0;i<N;i++){ARR[i]=nl();}return ARR;}
    static boolean multipleTC=false;
 
/////////////////////////////////////////////////////////////////////////////////////////////////////////
    static class AnotherReader{BufferedReader br; StringTokenizer st;
    AnotherReader()throws FileNotFoundException{
    br=new BufferedReader(new InputStreamReader(System.in));}
    AnotherReader(int a)throws FileNotFoundException{
    br = new BufferedReader(new FileReader("input.txt"));}
    String next()throws IOException{
    while (st == null || !st.hasMoreElements()) {try{
    st = new StringTokenizer(br.readLine());}
    catch (IOException  e){ e.printStackTrace(); }}
    return st.nextToken(); } int nextInt() throws IOException{
    return Integer.parseInt(next());}
    long nextLong() throws IOException
    {return Long.parseLong(next());}
    double nextDouble()throws IOException { return Double.parseDouble(next()); }
    String nextLine() throws IOException{ String str = ""; try{
    str = br.readLine();} catch (IOException e){
    e.printStackTrace();} return str;}}
    
/////////////////////////////////////////////////////////////////////////////////////////////////////////////
} public class Main
{  
    
    public static void process()throws IOException
    {
     for(int i=0;i<5;i++)
       {
        long x=nl();
        if(x==0)
        {
            pn(i+1);break;
        }
       }
   
    }
    static AnotherReader sc;
    static PrintWriter out;
    public static void main(String[]args)throws IOException
    {
        out = new PrintWriter(System.out);
        sc=new AnotherReader();
        boolean oj = true;
         //PrintWriter out=new PrintWriter("output");
        //oj = System.getProperty("ONLINE_JUDGE") != null;
        //if(!oj) sc=new AnotherReader(100);
      
         //int T=ni(); while(T-->0)
            process();
           
      
        long s = System.currentTimeMillis();
      
        out.flush();
        if(!oj)
            System.out.println(System.currentTimeMillis()-s+"ms");
        System.out.close();  
    }
    static void sort(long arr[],int n)
    {
    shuffle(arr,n);
    Arrays.sort(arr);
    }
    static void shuffle(long arr[],int n)
    {
        Random r=new Random();
        for(int i=0;i<n;i++)
        {
          long temp=arr[i];
          int pos=i+r.nextInt(n-i);
          arr[i]=arr[pos];
          arr[pos]=temp;
        }
    }
 
    static void pn(Object o){out.println(o);}
    static void p(Object o){out.print(o);}
    static void pni(Object o){out.println(o);System.out.flush();}
    static int ni()throws IOException{return sc.nextInt();}
    static long nl()throws IOException{return sc.nextLong();}
    static double nd()throws IOException{return sc.nextDouble();}
    static String nln()throws IOException{return sc.nextLine();}
    static String nn()throws IOException{return sc.next();}
    static long gcd(long a, long b)throws IOException{return (b==0)?a:gcd(b,a%b);}
    static int gcd(int a, int b)throws IOException{return (b==0)?a:gcd(b,a%b);}
    static int bit(long n)throws IOException{return (n==0)?0:(1+bit(n&(n-1)));}
    static int[] iarr(int N)throws IOException{int[]ARR=new int[N];for(int i=0;i<N;i++){ARR[i]=ni();}return ARR;}
    static long[] larr(int N)throws IOException{long[]ARR=new long[N];for(int i=0;i<N;i++){ARR[i]=nl();}return ARR;}
    static boolean multipleTC=false;
 
/////////////////////////////////////////////////////////////////////////////////////////////////////////
    static class AnotherReader{BufferedReader br; StringTokenizer st;
    AnotherReader()throws FileNotFoundException{
    br=new BufferedReader(new InputStreamReader(System.in));}
    AnotherReader(int a)throws FileNotFoundException{
    br = new BufferedReader(new FileReader("input.txt"));}
    String next()throws IOException{
    while (st == null || !st.hasMoreElements()) {try{
    st = new StringTokenizer(br.readLine());}
    catch (IOException  e){ e.printStackTrace(); }}
    return st.nextToken(); } int nextInt() throws IOException{
    return Integer.parseInt(next());}
    long nextLong() throws IOException
    {return Long.parseLong(next());}
    double nextDouble()throws IOException { return Double.parseDouble(next()); }
    String nextLine() throws IOException{ String str = ""; try{
    str = br.readLine();} catch (IOException e){
    e.printStackTrace();} return str;}}
    
/////////////////////////////////////////////////////////////////////////////////////////////////////////////
} Main
import java.util.*;
import java.io.*;
import java.math.*;
/*
javac Main.java
java Main > a.txt
*/
public class Main
{  
    
    public static void process()throws IOException
    {
     for(int i=0;i<5;i++)
       {
        long x=nl();
        if(x==0)
        {
            pn(i+1);break;
        }
       }
   
    }
    static AnotherReader sc;
    static PrintWriter out;
    public static void main(String[]args)throws IOException
    {
        out = new PrintWriter(System.out);
        sc=new AnotherReader();
        boolean oj = true;
         //PrintWriter out=new PrintWriter("output");
        //oj = System.getProperty("ONLINE_JUDGE") != null;
        //if(!oj) sc=new AnotherReader(100);
      
         //int T=ni(); while(T-->0)
            process();
           
      
        long s = System.currentTimeMillis();
      
        out.flush();
        if(!oj)
            System.out.println(System.currentTimeMillis()-s+"ms");
        System.out.close();  
    }
    static void sort(long arr[],int n)
    {
    shuffle(arr,n);
    Arrays.sort(arr);
    }
    static void shuffle(long arr[],int n)
    {
        Random r=new Random();
        for(int i=0;i<n;i++)
        {
          long temp=arr[i];
          int pos=i+r.nextInt(n-i);
          arr[i]=arr[pos];
          arr[pos]=temp;
        }
    }
 
    static void pn(Object o){out.println(o);}
    static void p(Object o){out.print(o);}
    static void pni(Object o){out.println(o);System.out.flush();}
    static int ni()throws IOException{return sc.nextInt();}
    static long nl()throws IOException{return sc.nextLong();}
    static double nd()throws IOException{return sc.nextDouble();}
    static String nln()throws IOException{return sc.nextLine();}
    static String nn()throws IOException{return sc.next();}
    static long gcd(long a, long b)throws IOException{return (b==0)?a:gcd(b,a%b);}
    static int gcd(int a, int b)throws IOException{return (b==0)?a:gcd(b,a%b);}
    static int bit(long n)throws IOException{return (n==0)?0:(1+bit(n&(n-1)));}
    static int[] iarr(int N)throws IOException{int[]ARR=new int[N];for(int i=0;i<N;i++){ARR[i]=ni();}return ARR;}
    static long[] larr(int N)throws IOException{long[]ARR=new long[N];for(int i=0;i<N;i++){ARR[i]=nl();}return ARR;}
    static boolean multipleTC=false;
 
/////////////////////////////////////////////////////////////////////////////////////////////////////////
    static class AnotherReader{BufferedReader br; StringTokenizer st;
    AnotherReader()throws FileNotFoundException{
    br=new BufferedReader(new InputStreamReader(System.in));}
    AnotherReader(int a)throws FileNotFoundException{
    br = new BufferedReader(new FileReader("input.txt"));}
    String next()throws IOException{
    while (st == null || !st.hasMoreElements()) {try{
    st = new StringTokenizer(br.readLine());}
    catch (IOException  e){ e.printStackTrace(); }}
    return st.nextToken(); } int nextInt() throws IOException{
    return Integer.parseInt(next());}
    long nextLong() throws IOException
    {return Long.parseLong(next());}
    double nextDouble()throws IOException { return Double.parseDouble(next()); }
    String nextLine() throws IOException{ String str = ""; try{
    str = br.readLine();} catch (IOException e){
    e.printStackTrace();} return str;}}
    
/////////////////////////////////////////////////////////////////////////////////////////////////////////////
}
    
    