import java.io*;
class problmeaUnu{
	public static viod main(String args[]){
int contor=0;
try{ FileReader fr=new FileReader("raport.txt");
for(;;){
int cod=fr.read();
if(cod==-1)break;
if((char)cod==1||(char)=='3'||(char)=='5'||(char)=='7') contor++;}
catch(IOException e){e.print Stack Trace();
System.exit(1);}
System.out.println(contor);


}}}