Selection sort.

for ( i = 0 ; i <= 3 ; i++ )
 {
  for ( j = i + 1 ; j <= 4 ; j++ )
  {
   if ( arr[i] > arr[j] )
   {
    temp = arr[i] ;
    arr[i] = arr[j] ;
    arr[j] = temp ;
   }
  }
 }