java - Spotify: "Best Before" Error -

so i, many others, have tried solve problem. believe have code correct, , have tested many, many, many dates on this. however, when send .java file, .jar file, , .class file guys @ spotify, continually says

we have tested solution, , while doing unfortunately discovered following error:
run time error
linkage error

what have works fine on system. guys have ideas on how can stop getting run time , linkage errors? code below:

package spotifychallenges;  import java.text.parseexception; import java.text.simpledateformat; import java.util.date; import java.util.scanner; import java.util.vector;  public class spotifychallenges {  public static void main(string[] args) throws parseexception {     vector approvedyears = new vector();     vector approvedmonths = new vector();     vector zeroesapplied = new vector();     vector approveddates = new vector();     vector earliestdate = new vector();     vector earliestdatecheck = new vector();      scanner scanner = new scanner(system.in);     system.out.println("enter date: ");     string input = scanner.nextline();      string splitinput[] = input.split("/");     string firstinput = splitinput[0];     string secondinput = splitinput[1];     string thirdinput = splitinput[2];      vector totalpossible = new vector();     totalpossible.add(firstinput + "-" + secondinput + "-" + thirdinput);     totalpossible.add(firstinput + "-" + thirdinput + "-" + secondinput);     totalpossible.add(secondinput + "-" + firstinput + "-" + thirdinput);     totalpossible.add(secondinput + "-" + thirdinput + "-" + firstinput);     totalpossible.add(thirdinput + "-" + firstinput + "-" + secondinput);     totalpossible.add(thirdinput + "-" + secondinput + "-" + firstinput);      (int = 0; < totalpossible.size(); i++) {         //gets possible date         string datepossible = totalpossible.elementat(i).tostring();         //splits possible date         string datepossiblesplit[] = datepossible.split("-");          if (datepossiblesplit[0].length() == 1) {             datepossiblesplit[0] = "200" + datepossiblesplit[0];         }         if (datepossiblesplit[0].length() == 2) {             datepossiblesplit[0] = "20" + datepossiblesplit[0];         }         if (datepossiblesplit[0].length() == 4) {         }          int datepossibleint = integer.parseint(datepossiblesplit[0].tostring());          if (datepossibleint < 2000 || datepossibleint > 2999) {         } else {             approvedyears.addelement(datepossible);         }     }      (int = 0; < approvedyears.size(); i++) {         string datepossible2 = approvedyears.elementat(i).tostring();          string datepossible2split[] = datepossible2.split("-");          if (datepossible2split[1].length() == 1) {             datepossible2split[1] = "0" + datepossible2split[0];         }         if (datepossible2split[1].length() == 2) {         }          int datepossible2splitint = integer.parseint(datepossible2split[1].tostring());          if (datepossible2splitint > 12 || datepossible2splitint < 1) {         } else {             approvedmonths.addelement(datepossible2);         }     }      (int = 0; < approvedmonths.size(); i++) {            string datepossiblefinal = approvedmonths.elementat(i).tostring();          string datepossiblefinalsplit[] = datepossiblefinal.split("-");          if (datepossiblefinalsplit[0].length() == 1) {             datepossiblefinalsplit[0] = "200" + datepossiblefinalsplit[0];         }         if (datepossiblefinalsplit[0].length() == 2) {             datepossiblefinalsplit[0] = "20" + datepossiblefinalsplit[0];         }         if (datepossiblefinalsplit[0].length() == 4) {         }          if (datepossiblefinalsplit[1].length() == 1) {             datepossiblefinalsplit[1] = 0 + "" + datepossiblefinalsplit[1];         }         if (datepossiblefinalsplit[1].length() == 2) {         }          string zeroesin = datepossiblefinalsplit[0] + "-" +         datepossiblefinalsplit[1] + "-" + datepossiblefinalsplit[2];         zeroesapplied.addelement(zeroesin);      }      (int = 0; < zeroesapplied.size(); i++) {         boolean leapyear;                    string finalpossible = zeroesapplied.elementat(i).tostring();          string finalpossiblesplit[] = finalpossible.split("-");         if (finalpossiblesplit[2].length() == 1) {             finalpossiblesplit[2] = 0 + "" + finalpossiblesplit[2];         }          string whatweadd = finalpossiblesplit[0] + "-" +          finalpossiblesplit[1] + "-" + finalpossiblesplit[2];          int year = integer.parseint(finalpossiblesplit[0]);         int month = integer.parseint(finalpossiblesplit[1]);         int day = integer.parseint(finalpossiblesplit[2]);         if (year % 4 == 0) {             if (year % 100 == 0) {                 if (year % 400 == 0) {                     leapyear = true;                 } else {                     leapyear = false;                 }             } else {                 leapyear = true;             }         } else {             leapyear = false;         }          if (leapyear == true) {             //31 day months             if (month == 1 || month == 3 || month == 5 || month == 7 ||              month == 8 || month == 10 || month == 12) {                 if (day < 1 || day > 31) {                 } else {                     approveddates.add(whatweadd);                 }                 //30 day months             }             if (month == 4 || month == 6 || month == 9 || month == 11) {                 if (day < 1 || day > 30) {                 } else {                     approveddates.add(whatweadd);                 }                 //february             }             if (month == 2) {                 if (day < 1 || day > 29) {                 } else {                     approveddates.add(whatweadd);                 }             }         }         if (leapyear == false) {             //31 day months             if (month == 1 || month == 3 || month == 5 || month == 7 ||                 month == 8 || month == 10 || month == 12) {                 if (day < 1 || day > 31) {                 } else {                     approveddates.add(whatweadd);                 }                 //30 day months             }             if (month == 4 || month == 6 || month == 9 || month == 11) {                 if (day < 1 || day > 30) {                 } else {                     approveddates.add(whatweadd);                 }                 //february             }             if (month == 2) {                 if (day < 1 || day > 28) {                 } else {                     approveddates.add(whatweadd);                 }             }         }     }     int sizecheck = approveddates.size();     if (sizecheck == 0) {         earliestdate.add(input + " illegal");     }     if (sizecheck == 1) {         earliestdate.add(         approveddates.elementat(0).tostring().replace("]", "").replace("[", ""));     } else {         (int = 0; < approveddates.size(); i++) {             earliestdatecheck.add(approveddates.elementat(i));         }     }     if (earliestdatecheck.size() >= 2) {         (int = 0; < earliestdatecheck.size() - 1; i++) {             simpledateformat form = new simpledateformat("yyyy-mm-dd");             vector setter = new vector();             date datecheck = form.parse(earliestdatecheck.elementat(i).tostring());             date datecheck2 = form.parse(                  earliestdatecheck.elementat(i + 1).tostring());              if (datecheck.before(datecheck2)) {                 setter.add(earliestdatecheck.elementat(i));             }             if (datecheck.equals(datecheck2)) {                 setter.add(earliestdatecheck.elementat(i));             }if(datecheck.after(datecheck2)){                 setter.add(earliestdatecheck.elementat(i+1));             }                earliestdate.add(setter.elementat(0).tostring());         }     }     system.out.println(earliestdate.elementat(0)); } } 

what have caused linkage or runtime error?