Salīdzināt vairāku līmeņu saistīto sarakstu (pēc dziļuma)

Salīdzināt vairāku līmeņu saistīto sarakstu (pēc dziļuma)

Dots saistīts saraksts, kurā papildus  nākamais  rādītājs katram mezglam ir a  bērns  rādītājs, kas var norādīt vai nenorādīt uz atsevišķu sarakstu. Šajos pakārtotajos sarakstos var būt  viens vai vairāki  savus bērnus ražot a  daudzlīmeņu  saistītais saraksts. Ņemot vērā  galvu  no  pirmais līmenis  no saraksta. Uzdevums ir  saplacināt  sarakstu, lai visi mezgli parādītos a  vienlīmeņa  saistītais saraksts. Izlīdziniet sarakstu tā, lai visi mezgli pie  pirmais līmenis  vajadzētu nākt  vispirms tad mezgli  otrais  līmenis un tā tālāk.

Piemēri:

Ievade:

2_5


Izvade: 1->4->6->2->5->7->3->8
Paskaidrojums: Daudzlīmeņu saistītais saraksts ir saplacināts, jo tajā nav pakārtotu norādes.

Mēs esam apsprieduši daudzlīmeņu saistītā saraksta saplacināšana kur mezgliem ir divas norādes uz leju un nākamo. Iepriekšējā ierakstā mēs saplacināts saistīto sarakstu līmenī. Kā saplacināt saistīto sarakstu, kad mums vienmēr ir jāapstrādā rādītājs uz leju pirms nākamā katrā mezglā.

Satura rādītājs

[Paredzamā pieeja] Rekursijas izmantošana - O(n) laiks un O(n) telpa

Pieeja ir rekursīvi saplacināt a vairāklīmeņu saistīts sarakstu, šķērsojot katru mezglu un tā pakārtotos mezglus. Pirmkārt saplaciniet bērnu sarakstu izmantojot rekursiju. Kad bērnu saraksts ir saplacināts, pārejiet uz nākamais mezgls secībā. Šķērsošanas laikā uzturēt a atsauce uz iepriekš apmeklētais mezgls un saistīt to ar pašreizējo mezglu. Šis process nodrošina, ka visi dažādu līmeņu mezgli ir savienoti a viens lineārs saraksts vienlaikus saglabājot dziļuma secība.

C++
   // A C++ program to flatten a multi-   // linked list depth-wise   #include          using     namespace     std  ;   class     Node     {      public  :      int     data  ;      Node     *  next  ;      Node     *  down  ;      Node  (  int     x  )     {      data     =     x  ;      next     =     down     =     nullptr  ;      }   };   void     flattenList  (  Node     *  curr       Node     *&  prev  )     {      if     (  curr     ==     nullptr  )      return  ;      // Add the current element to the list.      if     (  prev     !=     nullptr  )      prev  ->  next     =     curr  ;      prev     =     curr  ;      // Store the next pointer      Node     *  next     =     curr  ->  next  ;      // Recursively add the bottom list      flattenList  (  curr  ->  down       prev  );      // Recursively add the next list      flattenList  (  next       prev  );   }   void     printList  (  Node     *  head  )     {      Node     *  curr     =     head  ;      while     (  curr     !=     nullptr  )     {      cout      < <     curr  ->  data      < <     ' '  ;      curr     =     curr  ->  next  ;      }      cout      < <     endl  ;   }   int     main  ()     {      // Create a hard coded multi-linked list.      // 5 -> 10 -> 19 -> 28      // | |      // 7 22      // | |      // 8 50      // |      // 30      Node     *  head     =     new     Node  (  5  );      head  ->  down     =     new     Node  (  7  );      head  ->  down  ->  down     =     new     Node  (  8  );      head  ->  down  ->  down  ->  down     =     new     Node  (  30  );      head  ->  next     =     new     Node  (  10  );      head  ->  next  ->  next     =     new     Node  (  19  );      head  ->  next  ->  next  ->  down     =     new     Node  (  22  );      head  ->  next  ->  next  ->  down  ->  down     =     new     Node  (  50  );      head  ->  next  ->  next  ->  next     =     new     Node  (  28  );      Node     *  prev     =     nullptr  ;      flattenList  (  head       prev  );      printList  (  head  );      return     0  ;   }   
Java
   // A Java program to flatten a multi-   // linked list depth-wise   class   Node     {      int     data  ;      Node     next       down  ;      Node  (  int     x  )     {      data     =     x  ;      next     =     down     =     null  ;      }   }   class   GfG     {          static     void     flattenList  (  Node     curr       Node  []     prev  )     {      if     (  curr     ==     null  )      return  ;      // Add the current element to the list.      if     (  prev  [  0  ]     !=     null  )      prev  [  0  ]  .  next     =     curr  ;      prev  [  0  ]     =     curr  ;      // Store the next pointer      Node     next     =     curr  .  next  ;      // Recursively add the bottom list      flattenList  (  curr  .  down       prev  );      // Recursively add the next list      flattenList  (  next       prev  );      }      static     void     printList  (  Node     head  )     {      Node     curr     =     head  ;      while     (  curr     !=     null  )     {      System  .  out  .  print  (  curr  .  data     +     ' '  );      curr     =     curr  .  next  ;      }      System  .  out  .  println  ();      }      public     static     void     main  (  String  []     args  )     {          // Create a hard coded multi-linked list.      // 5 -> 10 -> 19 -> 28      // | |      // 7 22      // | |      // 8 50      // |      // 30      Node     head     =     new     Node  (  5  );      head  .  down     =     new     Node  (  7  );      head  .  down  .  down     =     new     Node  (  8  );      head  .  down  .  down  .  down     =     new     Node  (  30  );      head  .  next     =     new     Node  (  10  );      head  .  next  .  next     =     new     Node  (  19  );      head  .  next  .  next  .  down     =     new     Node  (  22  );      head  .  next  .  next  .  down  .  down     =     new     Node  (  50  );      head  .  next  .  next  .  next     =     new     Node  (  28  );      Node  []     prev     =     new     Node  [  1  ]  ;      flattenList  (  head       prev  );      printList  (  head  );      }   }   
Python
   # A Python program to flatten a multi-   # linked list depth-wise   class   Node  :   def   __init__  (  self     x  ):   self  .  data   =   x   self  .  next   =   None   self  .  down   =   None   def   flatten_list  (  curr     prev  ):   if   curr   is   None  :   return   # Add the current element to the list.   if   prev  [  0  ]   is   not   None  :   prev  [  0  ]  .  next   =   curr   prev  [  0  ]   =   curr   # Store the next pointer   next_node   =   curr  .  next   # Recursively add the bottom list   flatten_list  (  curr  .  down     prev  )   # Recursively add the next list   flatten_list  (  next_node     prev  )   def   print_list  (  head  ):   curr   =   head   while   curr   is   not   None  :   print  (  curr  .  data     end  =  ' '  )   curr   =   curr  .  next   print  ()   if   __name__   ==   '__main__'  :   # Create a hard coded multi-linked list.   # 5 -> 10 -> 19 -> 28   # | |   # 7 22   # | |   # 8 50   # |   # 30   head   =   Node  (  5  )   head  .  down   =   Node  (  7  )   head  .  down  .  down   =   Node  (  8  )   head  .  down  .  down  .  down   =   Node  (  30  )   head  .  next   =   Node  (  10  )   head  .  next  .  next   =   Node  (  19  )   head  .  next  .  next  .  down   =   Node  (  22  )   head  .  next  .  next  .  down  .  down   =   Node  (  50  )   head  .  next  .  next  .  next   =   Node  (  28  )   prev   =   [  None  ]   flatten_list  (  head     prev  )   print_list  (  head  )   
C#
   // A C# program to flatten a multi-   // linked list depth-wise   using     System  ;   class     Node     {      public     int     data  ;      public     Node     next       down  ;      public     Node  (  int     x  )     {      data     =     x  ;      next     =     down     =     null  ;      }   }   class     GfG     {      static     void     FlattenList  (  Node     curr       ref     Node     prev  )     {      if     (  curr     ==     null  )      return  ;      // Add the current element to the list.      if     (  prev     !=     null  )      prev  .  next     =     curr  ;      prev     =     curr  ;      // Store the next pointer      Node     next     =     curr  .  next  ;      // Recursively add the bottom list      FlattenList  (  curr  .  down       ref     prev  );      // Recursively add the next list      FlattenList  (  next       ref     prev  );      }      static     void     PrintList  (  Node     head  )     {      Node     curr     =     head  ;      while     (  curr     !=     null  )     {      Console  .  Write  (  curr  .  data     +     ' '  );      curr     =     curr  .  next  ;      }      Console  .  WriteLine  ();      }      static     void     Main  (  string  []     args  )     {      // Create a hard coded multi-linked list.      // 5 -> 10 -> 19 -> 28      // | |      // 7 22      // | |      // 8 50      // |      // 30      Node     head     =     new     Node  (  5  );      head  .  down     =     new     Node  (  7  );      head  .  down  .  down     =     new     Node  (  8  );      head  .  down  .  down  .  down     =     new     Node  (  30  );      head  .  next     =     new     Node  (  10  );      head  .  next  .  next     =     new     Node  (  19  );      head  .  next  .  next  .  down     =     new     Node  (  22  );      head  .  next  .  next  .  down  .  down     =     new     Node  (  50  );      head  .  next  .  next  .  next     =     new     Node  (  28  );      Node     prev     =     null  ;      FlattenList  (  head       ref     prev  );      PrintList  (  head  );      }   }   
JavaScript
   // A Javascript program to flatten a multi-   // linked list depth-wise   class     Node     {      constructor  (  x  )     {      this  .  data     =     x  ;      this  .  next     =     null  ;      this  .  down     =     null  ;      }   }   function     flattenList  (  curr       prev  )     {      if     (  curr     ===     null  )     return  ;      // Add the current element to the list.      if     (  prev  [  0  ]     !==     null  )     prev  [  0  ].  next     =     curr  ;      prev  [  0  ]     =     curr  ;      // Store the next pointer      let     next     =     curr  .  next  ;      // Recursively add the bottom list      flattenList  (  curr  .  down       prev  );      // Recursively add the next list      flattenList  (  next       prev  );   }   function     printList  (  head  )     {      let     curr     =     head  ;      while     (  curr     !==     null  )     {      console  .  log  (  curr  .  data  );      curr     =     curr  .  next  ;      }   }   // Create a hard coded multi-linked list.   // 5 -> 10 -> 19 -> 28   // | |   // 7 22   // | |   // 8 50   // |   // 30   let     head     =     new     Node  (  5  );   head  .  down     =     new     Node  (  7  );   head  .  down  .  down     =     new     Node  (  8  );   head  .  down  .  down  .  down     =     new     Node  (  30  );   head  .  next     =     new     Node  (  10  );   head  .  next  .  next     =     new     Node  (  19  );   head  .  next  .  next  .  down     =     new     Node  (  22  );   head  .  next  .  next  .  down  .  down     =     new     Node  (  50  );   head  .  next  .  next  .  next     =     new     Node  (  28  );   let     prev     =     [  null  ];   flattenList  (  head       prev  );   printList  (  head  );   

Izvade
5 7 8 30 10 19 22 50 28  

[Alternatīva pieeja] Stack izmantošana — O(n) laiks un O(n) telpa

Pieeja ir šķērsot daudzlīmeņu saistītais saraksts izmantojot a kaudze . Sāciet ar spiežot uz galvas mezgls uz kaudzes. Tad, kamēr kaudze nav tukša pop augšējo mezglu un apstrādājiet to. Katram mezglam spiediet nākamās un lejupvērstās norādes (ja tādi ir) uz kaudzes. Šī procesa laikā savienot pašreizējo mezglu ar iepriekšējo mezglu saraksta uzturēšana saplacinātā veidā. Šķērsošana nodrošina, ka mezgli no visiem līmeņiem ir savienoti a viena līmeņa saistītais saraksts saglabājot dziļuma kārtību.

C++
   // A C++ program to flatten a multi-   // linked list depth-wise using stack   #include          using     namespace     std  ;   class     Node     {      public  :      int     data  ;      Node     *  next  ;      Node     *  down  ;      Node  (  int     x  )     {      data     =     x  ;      next     =     down     =     nullptr  ;      }   };   void     flattenList  (  Node     *  head  )     {      if     (  head     ==     nullptr  )      return  ;      stack   <  Node     *>     st  ;      st  .  push  (  head  );      Node     *  prev     =     nullptr  ;      while     (  !  st  .  empty  ())     {      Node     *  curr     =     st  .  top  ();      st  .  pop  ();      // Push the next node first      if     (  curr  ->  next     !=     nullptr  )      st  .  push  (  curr  ->  next  );      // Push the bottom node into stack      if     (  curr  ->  down     !=     nullptr  )      st  .  push  (  curr  ->  down  );      // Add the current element to the list      if     (  prev     !=     nullptr  )      prev  ->  next     =     curr  ;      prev     =     curr  ;      }   }   void     printList  (  Node     *  head  )     {      Node     *  curr     =     head  ;      while     (  curr     !=     nullptr  )     {      cout      < <     curr  ->  data      < <     ' '  ;      curr     =     curr  ->  next  ;      }      cout      < <     endl  ;   }   int     main  ()     {      // Create a hard coded multi-linked list.      // 5 -> 10 -> 19 -> 28      // | |      // 7 22      // | |      // 8 50      // |      // 30      Node     *  head     =     new     Node  (  5  );      head  ->  down     =     new     Node  (  7  );      head  ->  down  ->  down     =     new     Node  (  8  );      head  ->  down  ->  down  ->  down     =     new     Node  (  30  );      head  ->  next     =     new     Node  (  10  );      head  ->  next  ->  next     =     new     Node  (  19  );      head  ->  next  ->  next  ->  down     =     new     Node  (  22  );      head  ->  next  ->  next  ->  down  ->  down     =     new     Node  (  50  );      head  ->  next  ->  next  ->  next     =     new     Node  (  28  );      flattenList  (  head  );      printList  (  head  );      return     0  ;   }   
Java
   // A Java program to flatten a multi-   // linked list depth-wise using stack   import     java.util.Stack  ;   class   Node     {      int     data  ;      Node     next       down  ;      Node  (  int     x  )     {      data     =     x  ;      next     =     down     =     null  ;      }   }   class   GfG     {      static     void     flattenList  (  Node     head  )     {      if     (  head     ==     null  )      return  ;      Stack   <  Node  >     stack     =     new     Stack   <>  ();      stack  .  push  (  head  );      Node     prev     =     null  ;      while     (  !  stack  .  isEmpty  ())     {      Node     curr     =     stack  .  pop  ();      // Push the next node first      if     (  curr  .  next     !=     null  )      stack  .  push  (  curr  .  next  );      // Push the bottom node into stack      if     (  curr  .  down     !=     null  )      stack  .  push  (  curr  .  down  );      // Add the current element to the list      if     (  prev     !=     null  )      prev  .  next     =     curr  ;      prev     =     curr  ;      }      }      static     void     printList  (  Node     head  )     {      Node     curr     =     head  ;      while     (  curr     !=     null  )     {      System  .  out  .  print  (  curr  .  data     +     ' '  );      curr     =     curr  .  next  ;      }      System  .  out  .  println  ();      }      public     static     void     main  (  String  []     args  )     {      // Create a hard coded multi-linked list.      // 5 -> 10 -> 19 -> 28      // | |      // 7 22      // | |      // 8 50      // |      // 30      Node     head     =     new     Node  (  5  );      head  .  down     =     new     Node  (  7  );      head  .  down  .  down     =     new     Node  (  8  );      head  .  down  .  down  .  down     =     new     Node  (  30  );      head  .  next     =     new     Node  (  10  );      head  .  next  .  next     =     new     Node  (  19  );      head  .  next  .  next  .  down     =     new     Node  (  22  );      head  .  next  .  next  .  down  .  down     =     new     Node  (  50  );      head  .  next  .  next  .  next     =     new     Node  (  28  );      flattenList  (  head  );      printList  (  head  );      }   }   
Python
   # A Python program to flatten a multi-   # linked list depth-wise using stack   class   Node  :   def   __init__  (  self     x  ):   self  .  data   =   x   self  .  next   =   None   self  .  down   =   None   def   flatten_list  (  head  ):   if   head   is   None  :   return   stack   =   [  head  ]   prev   =   None   while   stack  :   curr   =   stack  .  pop  ()   # Push the next node first   if   curr  .  next  :   stack  .  append  (  curr  .  next  )   # Push the bottom node into stack   if   curr  .  down  :   stack  .  append  (  curr  .  down  )   # Add the current element to the list   if   prev  :   prev  .  next   =   curr   prev   =   curr   def   print_list  (  head  ):   curr   =   head   while   curr  :   print  (  curr  .  data     end  =  ' '  )   curr   =   curr  .  next   print  ()   if   __name__   ==   '__main__'  :   # Create a hard coded multi-linked list.   # 5 -> 10 -> 19 -> 28   # | |   # 7 22   # | |   # 8 50   # |   # 30   head   =   Node  (  5  )   head  .  down   =   Node  (  7  )   head  .  down  .  down   =   Node  (  8  )   head  .  down  .  down  .  down   =   Node  (  30  )   head  .  next   =   Node  (  10  )   head  .  next  .  next   =   Node  (  19  )   head  .  next  .  next  .  down   =   Node  (  22  )   head  .  next  .  next  .  down  .  down   =   Node  (  50  )   head  .  next  .  next  .  next   =   Node  (  28  )   flatten_list  (  head  )   print_list  (  head  )   
C#
   // A C# program to flatten a multi-   // linked list depth-wise using stack   using     System  ;   using     System.Collections.Generic  ;   class     Node     {      public     int     data  ;      public     Node     next       down  ;      public     Node  (  int     x  )     {      data     =     x  ;      next     =     down     =     null  ;      }   }   class     GfG     {      static     void     FlattenList  (  Node     head  )     {      if     (  head     ==     null  )      return  ;      Stack   <  Node  >     stack     =     new     Stack   <  Node  >  ();      stack  .  Push  (  head  );      Node     prev     =     null  ;      while     (  stack  .  Count     >     0  )     {      Node     curr     =     stack  .  Pop  ();      // Push the next node first      if     (  curr  .  next     !=     null  )      stack  .  Push  (  curr  .  next  );      // Push the bottom node into stack      if     (  curr  .  down     !=     null  )      stack  .  Push  (  curr  .  down  );      // Add the current element to the list      if     (  prev     !=     null  )      prev  .  next     =     curr  ;      prev     =     curr  ;      }      }      static     void     PrintList  (  Node     head  )     {      Node     curr     =     head  ;      while     (  curr     !=     null  )     {      Console  .  Write  (  curr  .  data     +     ' '  );      curr     =     curr  .  next  ;      }      Console  .  WriteLine  ();      }      static     void     Main  (  string  []     args  )     {          // Create a hard coded multi-linked list.      // 5 -> 10 -> 19 -> 28      // | |      // 7 22      // | |      // 8 50      // |      // 30      Node     head     =     new     Node  (  5  );      head  .  down     =     new     Node  (  7  );      head  .  down  .  down     =     new     Node  (  8  );      head  .  down  .  down  .  down     =     new     Node  (  30  );      head  .  next     =     new     Node  (  10  );      head  .  next  .  next     =     new     Node  (  19  );      head  .  next  .  next  .  down     =     new     Node  (  22  );      head  .  next  .  next  .  down  .  down     =     new     Node  (  50  );      head  .  next  .  next  .  next     =     new     Node  (  28  );          FlattenList  (  head  );      PrintList  (  head  );      }   }   
JavaScript
   // A Javascript program to flatten a multi-   // linked list depth-wise using stack   class     Node     {      constructor  (  x  )     {      this  .  data     =     x  ;      this  .  next     =     null  ;      this  .  down     =     null  ;      }   }   function     flattenList  (  head  )     {      if     (  head     ===     null  )     return  ;      let     stack     =     [  head  ];      let     prev     =     null  ;      while     (  stack  .  length     >     0  )     {      let     curr     =     stack  .  pop  ();      // Push the next node first      if     (  curr  .  next     !==     null  )     stack  .  push  (  curr  .  next  );      // Push the bottom node into stack      if     (  curr  .  down     !==     null  )     stack  .  push  (  curr  .  down  );      // Add the current element to the list      if     (  prev     !==     null  )     prev  .  next     =     curr  ;      prev     =     curr  ;      }   }   function     printList  (  head  )     {      let     curr     =     head  ;      while     (  curr     !==     null  )     {      console  .  log  (  curr  .  data  );      curr     =     curr  .  next  ;      }   }   // Create a hard coded multi-linked list.   // 5 -> 10 -> 19 -> 28   // | |   // 7 22   // | |   // 8 50   // |   // 30   let     head     =     new     Node  (  5  );   head  .  down     =     new     Node  (  7  );   head  .  down  .  down     =     new     Node  (  8  );   head  .  down  .  down  .  down     =     new     Node  (  30  );   head  .  next     =     new     Node  (  10  );   head  .  next  .  next     =     new     Node  (  19  );   head  .  next  .  next  .  down     =     new     Node  (  22  );   head  .  next  .  next  .  down  .  down     =     new     Node  (  50  );   head  .  next  .  next  .  next     =     new     Node  (  28  );   flattenList  (  head  );   printList  (  head  );   

Izvade
5 7 8 30 10 19 22 50 28