#include          #include         #include         #include         using     namespace     std  ;   bool     checkPerm  (  vector   <  int  >&     a       vector   <  int  >&     b  )     {      queue   <  int  >     q1  ;      for     (  int     i     =     0  ;     i      <     a  .  size  ();     i  ++  )         q1  .  push  (  a  [  i  ]);      queue   <  int  >     q2  ;      for     (  int     i     =     0  ;     i      <     b  .  size  ();     i  ++  )      q2  .  push  (  b  [  i  ]);      stack   <  int  >     st  ;          // Dequeue all items one by one      while     (  !  q1  .  empty  ())     {      int     ele     =     q1  .  front  ();      q1  .  pop  ();          if     (  ele     ==     q2  .  front  ())     {          // If matches dequeue from output queue      q2  .  pop  ();          // Pop from stack while top matches q2 front      while     (  !  st  .  empty  ()     &&     !  q2  .  empty  ()     &&     st  .  top  ()     ==     q2  .  front  ())     {      st  .  pop  ();      q2  .  pop  ();      }      }      else     {      st  .  push  (  ele  );      }      }          return     q2  .  empty  ();   }   int     main  ()     {      vector   <  int  >     a     =     {  1       2       3  };      vector   <  int  >     b     =     {  3       2       1  };          if     (  checkPerm  (  a       b  ))      cout      < <     'true'      < <     endl  ;      else      cout      < <     'false'      < <     endl  ;      return     0  ;   }   

   import     java.util.LinkedList  ;   import     java.util.Queue  ;   import     java.util.Stack  ;   public     class   GfG     {      static     boolean     checkPerm  (  int  []     a       int  []     b  )     {      Queue   <  Integer  >     q1     =     new     LinkedList   <>  ();      for     (  int     i     =     0  ;     i      <     a  .  length  ;     i  ++  )         q1  .  add  (  a  [  i  ]  );      Queue   <  Integer  >     q2     =     new     LinkedList   <>  ();      for     (  int     i     =     0  ;     i      <     b  .  length  ;     i  ++  )      q2  .  add  (  b  [  i  ]  );      Stack   <  Integer  >     st     =     new     Stack   <>  ();          // Dequeue all items one by one      while     (  !  q1  .  isEmpty  ())     {      int     ele     =     q1  .  poll  ();          if     (  ele     ==     q2  .  peek  ())     {          // If matches dequeue from output queue      q2  .  poll  ();          // Pop from stack while top matches q2 front      while     (  !  st  .  isEmpty  ()     &&     !  q2  .  isEmpty  ()     &&     st  .  peek  ()     ==     q2  .  peek  ())     {      st  .  pop  ();      q2  .  poll  ();      }      }      else     {      st  .  push  (  ele  );      }      }          return     q2  .  isEmpty  ();      }      public     static     void     main  (  String  []     args  )     {      int  []     a     =     {  1       2       3  };      int  []     b     =     {  3       2       1  };          if     (  checkPerm  (  a       b  ))      System  .  out  .  println  (  'true'  );      else      System  .  out  .  println  (  'false'  );      }   }   

   from   collections   import   deque   def   checkPerm  (  a     b  ):   q1   =   deque  (  a  )   q2   =   deque  (  b  )   st   =   []   # Dequeue all items one by one   while   q1  :   ele   =   q1  .  popleft  ()   if   ele   ==   q2  [  0  ]:   # If matches dequeue from output queue   q2  .  popleft  ()   # Pop from stack while top matches q2 front   while   st   and   q2   and   st  [  -  1  ]   ==   q2  [  0  ]:   st  .  pop  ()   q2  .  popleft  ()   else  :   st  .  append  (  ele  )   return   not   q2   if   __name__   ==   '__main__'  :   a   =   [  1     2     3  ]   b   =   [  3     2     1  ]   if   checkPerm  (  a     b  ):   print  (  'true'  )   else  :   print  (  'false'  )   

   using     System  ;   using     System.Collections.Generic  ;   public     class     GfG     {      static     bool     checkPerm  (  int  []     a       int  []     b  )     {      Queue   <  int  >     q1     =     new     Queue   <  int  >  (  a  );      Queue   <  int  >     q2     =     new     Queue   <  int  >  (  b  );      Stack   <  int  >     st     =     new     Stack   <  int  >  ();          // Dequeue all items one by one      while     (  q1  .  Count     >     0  )     {      int     ele     =     q1  .  Dequeue  ();          if     (  ele     ==     q2  .  Peek  ())     {          // If matches dequeue from output queue      q2  .  Dequeue  ();          // Pop from stack while top matches q2 front      while     (  st  .  Count     >     0     &&     q2  .  Count     >     0     &&     st  .  Peek  ()     ==     q2  .  Peek  ())      {      st  .  Pop  ();      q2  .  Dequeue  ();      }      }      else      {      st  .  Push  (  ele  );      }      }          return     q2  .  Count     ==     0  ;      }      public     static     void     Main  ()     {      int  []     a     =     {     1       2       3     };      int  []     b     =     {     3       2       1     };          if     (  checkPerm  (  a       b  ))      Console  .  WriteLine  (  'true'  );      else      Console  .  WriteLine  (  'false'  );      }   }   

   function     checkPerm  (  a       b  )     {          // simulate queue with array      let     q1     =     a  ;             // simulate queue with array      let     q2     =     b  ;         let     st     =     [];      // pointer for front of q1      let     front1     =     0  ;             // pointer for front of q2      let     front2     =     0  ;             while     (  front1      <     q1  .  length  )     {      let     ele     =     q1  [  front1  ];      front1  ++  ;      if     (  ele     ===     q2  [  front2  ])     {      front2  ++  ;      // Pop from stack while top matches q2 front      while     (  st  .  length     >     0     &&     st  [  st  .  length     -     1  ]     ===     q2  [  front2  ])     {      st  .  pop  ();      front2  ++  ;      }      }     else     {      st  .  push  (  ele  );      }      }      return     front2     ===     q2  .  length  ;   }   // Driver Code   let     a     =     [  1       2       3  ];   let     b     =     [  3       2       1  ];   console  .  log  (  checkPerm  (  a       b  ));      

   #include          #include         #include         using     namespace     std  ;   bool     checkPerm  (  vector   <  int  >&     a       vector   <  int  >&     b  )     {      stack   <  int  >     st  ;      int     j     =     0  ;      for     (  int     i     =     0  ;     i      <     a  .  size  ();     i  ++  )     {          // Push top of a[] to stack      st  .  push  (  a  [  i  ]);      // Keep popping from stack while it      // matches front of the output queue      while     (  !  st  .  empty  ()     &&     st  .  top  ()     ==     b  [  j  ])     {      st  .  pop  ();      j  ++  ;      }      }      return     (  j     ==     b  .  size  ());   }   int     main  ()     {      vector   <  int  >     a     =     {  1       2       3  };      vector   <  int  >     b     =     {  2       1       3  };      cout      < <     (  checkPerm  (  a       b  )     ?     'true'     :     'false'  )      < <     endl  ;      return     0  ;   }   

   import     java.util.Stack  ;   public     class   GfG     {      static     boolean     checkPerm  (  int  []     a       int  []     b  )     {      Stack   <  Integer  >     st     =     new     Stack   <>  ();      int     j     =     0  ;      for     (  int     i     =     0  ;     i      <     a  .  length  ;     i  ++  )     {          // Push top of a[] to stack      st  .  push  (  a  [  i  ]  );      // Keep popping from stack while it      // matches front of the output array      while     (  !  st  .  isEmpty  ()     &&     st  .  peek  ().  equals  (  b  [  j  ]  ))     {      st  .  pop  ();      j  ++  ;      }      }      return     (  j     ==     b  .  length  );      }      public     static     void     main  (  String  []     args  )     {      int  []     a     =     {  1       2       3  };      int  []     b     =     {  2       1       3  };      System  .  out  .  println  (  checkPerm  (  a       b  )     ?     'true'     :     'false'  );      }   }   

   def   checkPerm  (  a     b  ):   st   =   []   j   =   0   for   i   in   range  (  len  (  a  )):   # Push top of a[] to stack   st  .  append  (  a  [  i  ])   # Keep popping from stack while it   # matches front of the output queue   while   st   and   st  [  -  1  ]   ==   b  [  j  ]:   st  .  pop  ()   j   +=   1   return   j   ==   len  (  b  )   if   __name__   ==   '__main__'  :   a   =   [  1     2     3  ]   b   =   [  2     1     3  ]   print  (  'true'   if   checkPerm  (  a     b  )   else   'false'  )   

   using     System  ;   using     System.Collections.Generic  ;   class     GfG     {      static     bool     checkPerm  (  int  []     a       int  []     b  )     {      Stack   <  int  >     stack     =     new     Stack   <  int  >  ();      int     j     =     0  ;      for     (  int     i     =     0  ;     i      <     a  .  Length  ;     i  ++  )     {      // Push top of a[] to stack      stack  .  Push  (  a  [  i  ]);      // Keep popping from stack while it matches b[j]      while     (  stack  .  Count     >     0     &&     stack  .  Peek  ()     ==     b  [  j  ])     {      stack  .  Pop  ();      j  ++  ;      }      }      return     j     ==     b  .  Length  ;      }      static     void     Main  ()     {      int  []     a     =     {     1       2       3     };      int  []     b     =     {     2       1       3     };      Console  .  WriteLine  (  checkPerm  (  a       b  )     ?     'true'     :     'false'  );      }   }   

   function     checkPerm  (  a       b  )     {      const     stack     =     [];      let     j     =     0  ;      for     (  let     i     =     0  ;     i      <     a  .  length  ;     i  ++  )     {          // Push top of a[] to stack      stack  .  push  (  a  [  i  ]);      // Keep popping from stack while it      // matches front of the output queue      while     (  stack  .  length     >     0     &&     stack  [  stack  .  length     -     1  ]     ===     b  [  j  ])     {      stack  .  pop  ();      j  ++  ;      }      }      return     j     ===     b  .  length  ;   }   //Driven Code   const     a     =     [  1       2       3  ];   const     b     =     [  2       1       3  ];   console  .  log  (  checkPerm  (  a       b  )     ?     'true'     :     'false'  );