POJ 3253 Fence Repair

解题思路:基于最小堆实现Haffman

NULL

   
     

    
      
    
      #include 
    
      <
    
      iostream
    
      >
    
      

    
      using
    
       
    
      namespace
    
       std;

    
      int
    
       n,plank[
    
      20001
    
      ];

    
      void
    
       heapAdjust(
    
      int
    
       s)
{
 
    
      int
    
       i,exp;
 
    
      for
    
      (i
    
      =
    
      s;i
    
      <=
    
      (n
    
      /
    
      2
    
      );)
 {
 exp
    
      =
    
      ((i
    
      *
    
      2
    
      +
    
      1
    
      )
    
      <=
    
      n
    
      &&
    
      plank[i
    
      *
    
      2
    
      +
    
      1
    
      ]
    
      <
    
      plank[i
    
      *
    
      2
    
      ])
    
      ?
    
      1
    
      :
    
      0
    
      ;
 
    
      if
    
      (plank[i]
    
      >
    
      plank[i
    
      *
    
      2
    
      +
    
      exp])
 swap(plank[i],plank[i
    
      *
    
      2
    
      +
    
      exp]),i
    
      =
    
      i
    
      *
    
      2
    
      +
    
      exp;
 
    
      else
    
       
    
      break
    
      ;
 }
}


    
      int
    
       main()
{
 
    
      int
    
       i,t;
 __int64 ans
    
      =
    
      0
    
      ;
 scanf(
    
      "
    
      %d
    
      "
    
      ,
    
      &
    
      n);
 
    
      for
    
      (i
    
      =
    
      1
    
      ;i
    
      <=
    
      n;i
    
      ++
    
      )scanf(
    
      "
    
      %d
    
      "
    
      ,
    
      &
    
      plank[i]);
 
    
      for
    
      (i
    
      =
    
      n
    
      /
    
      2
    
      ;i
    
      >=
    
      1
    
      ;i
    
      --
    
      )heapAdjust(i);
 
    
      while
    
       (n
    
      >
    
      1
    
      )
 {
 t
    
      =
    
      plank[
    
      1
    
      ];plank[
    
      1
    
      ]
    
      =
    
      plank[n];n
    
      --
    
      ;
 heapAdjust(
    
      1
    
      );
 t
    
      +=
    
      plank[
    
      1
    
      ];plank[
    
      1
    
      ]
    
      =
    
      t;
 heapAdjust(
    
      1
    
      );
 ans
    
      +=
    
      t;
 }
 printf(
    
      "
    
      %I64d\n
    
      "
    
      ,ans);
 
    
      return
    
       
    
      0
    
      ;
}