Java Selection Sort Confusion

Question

I don't understand what is happening in this code. Re-post from before with code included. Can someone please explain what is happening here? I understand conceptually that the list is being re-ordered one item at a time, but I just cant grasp this code.

import java.io*;

public class Example {

   public static void main(String[] args) throws IOException {

      int age[] = new int[10];
      int i, j;
      int smallest;
      int temp;
      String line; 
      BufferedReader in;
      in = new BUfferedReader(new InputStreamReader(System.in));
      for(i = 0; i<= 9; i++)
      {
       System.out.println("Enter an age: ");
       line = in.readline();
       age[i] = Integer.valueOf(line).intValue();
      }
      for(i = 0; i<= 9, i++) {
         smallest = i;
           for(j = 1; j<=9; j++)
             {
               if(age[j] < age[smallest]) {
                   smallest = j;
               }
             }
           for (i = 0; i<=9; i++)
           {
            System.out.println(age[i]);
           }
        }
    }
  }

Answer 1

This looks like an implementation of the Bubble Sort. There is a wide wealth of information on the topic of this classic (and inefficient!) algorithm both on The Internet and in books on the subject of fundamental algorithms.

Answer 2

import java.io*;

public class Example {

public static void main(String[] args) throws IOException {

  int age[] = new int[10];
  int i, j;
  int smallest;
  int temp;
  String line; 
  BufferedReader in;
  in = new BUfferedReader(new InputStreamReader(System.in));
  for(i = 0; i<= 9; i++)
  {
   System.out.println("Enter an age: ");
   line = in.readline();
   age[i] = Integer.valueOf(line).intValue();
  }
  for(i = 0; i<= 9, i++) {
     smallest = i;
       for(j = 1; j<=9; j++)// MISTAKE IS IN THIS LINE; YOU SHOULD START THE VALUE OF J FROM I+1(for(j = i+1; j<=9; j++)))
         {
           if(age[j] < age[smallest]) {
               smallest = j;
           }

         }
             //ALSO AFTER FINDING THE SMALLEST ELEMENT YOU HAVE TO SWAP THE SMALLEST ELEMENT WITH I ELEMENT
             /*int temp=age[i];
             age[i]=age[smallest];
             age[smallest]=temp*/
       for (i = 0; i<=9; i++)
       {
        System.out.println(age[i]);
       }
    }
}

}