java - string builder and string output -

although have converted output string, output on console "solution@3343c8b3". thanks.

public class solution {       public string converttotitle(int n) {          if (n < 1)             throw new illegalargumentexception("input wrong number");          stringbuilder sb = new stringbuilder();          while (n > 0) {             n--;             char ch = (char) (n % 26 + 'a');             n = n / 26;             sb.append(ch);         }          sb.reverse();         return sb.tostring();     } } 

the test class:

public class test {      public static void main(string[] args) {          int f = 2;          solution f1 = new solution();         f1.converttotitle(f);          system.out.println(f1);     } } 

you should print value returned method : converttotitle :

string title = f1.converttotitle(f); system.out.println(title); 

also, this might not concern @ time, system.out.println(f1); printing string provided default implementation of tostring in object class.

you should override tostring method in solution.