public class Series {

public static int checkStart(String abc){

int j=1;

while(j<=abc.length()/2){

Integer a=(Integer.parseInt(abc.substring(0, j))+1);

//System.out.println(a);

String av=a.toString();

int be=av.length();

Integer temp=a+1;

int le=temp.toString().length();

Integer w=a+1;

Integer c=a+2;

//System.out.println(c);

String cv=c.toString();

int de=cv.length();

if(av.equals(abc.substring(j, j+be))&&

w.toString().equals(abc.substring(j+be, j+be+w.toString().length()))

){

System.out.println(j+" we");

break;

}

else if(cv.equals(abc.substring(j+le, j+le+de))){

System.out.println(j+" ee");

break;

}

j++;

}

return j;

}

public static int Answer(String value){

int i=0;

while(i<value.length()){

int temp=Integer.parseInt(value.substring(i,i+Series.checkStart(value)));

Integer temp1=temp+1;

Integer temp2=temp+2;

String str=temp1.toString();

String str1=temp2.toString();

if(str.equals(value.substring(i+Series.checkStart(value),i+Series.checkStart(value)+str.length()))){

i=i+temp2.toString().length();

}else if((str1.equals(value.substring(i+Series.checkStart(value),i+Series.checkStart(value)+str1.length())))){

//System.out.println(temp2-1);

return temp2-1;

}else{

break;

}

}

return -1;

}

public static void main(String[] args){

String value="8101112";

//System.out.println(Series.checkStart(value));

//System.out.println(" ");

Series sc=new Series();

System.out.println(sc.Answer(value));

//System.out.println(sc.checkStart(value));

}

}