golang.org/x/exp@v0.0.0-20240506185415-9bf2ced13842/shootout/binary-tree.c (about)

     1  // +build ignore
     2  
     3  /*
     4  Redistribution and use in source and binary forms, with or without
     5  modification, are permitted provided that the following conditions are met:
     6  
     7      * Redistributions of source code must retain the above copyright
     8      notice, this list of conditions and the following disclaimer.
     9  
    10      * Redistributions in binary form must reproduce the above copyright
    11      notice, this list of conditions and the following disclaimer in the
    12      documentation and/or other materials provided with the distribution.
    13  
    14      * Neither the name of "The Computer Language Benchmarks Game" nor the
    15      name of "The Computer Language Shootout Benchmarks" nor the names of
    16      its contributors may be used to endorse or promote products derived
    17      from this software without specific prior written permission.
    18  
    19  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
    20  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
    21  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
    22  ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
    23  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
    24  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
    25  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
    26  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
    27  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
    28  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
    29  POSSIBILITY OF SUCH DAMAGE.
    30  */
    31  
    32  /* The Computer Language Shootout Benchmarks
    33     http://shootout.alioth.debian.org/
    34  
    35     contributed by Kevin Carson
    36     compilation:
    37         gcc -O3 -fomit-frame-pointer -funroll-loops -static binary-trees.c -lm
    38         icc -O3 -ip -unroll -static binary-trees.c -lm
    39  */
    40  
    41  #include <math.h>
    42  #include <stdio.h>
    43  #include <stdlib.h>
    44  
    45  
    46  typedef struct tn {
    47      struct tn*    left;
    48      struct tn*    right;
    49      long          item;
    50  } treeNode;
    51  
    52  
    53  treeNode* NewTreeNode(treeNode* left, treeNode* right, long item)
    54  {
    55      treeNode*    new;
    56  
    57      new = (treeNode*)malloc(sizeof(treeNode));
    58  
    59      new->left = left;
    60      new->right = right;
    61      new->item = item;
    62  
    63      return new;
    64  } /* NewTreeNode() */
    65  
    66  
    67  long ItemCheck(treeNode* tree)
    68  {
    69      if (tree->left == NULL)
    70          return tree->item;
    71      else
    72          return tree->item + ItemCheck(tree->left) - ItemCheck(tree->right);
    73  } /* ItemCheck() */
    74  
    75  
    76  treeNode* BottomUpTree(long item, unsigned depth)
    77  {
    78      if (depth > 0)
    79          return NewTreeNode
    80          (
    81              BottomUpTree(2 * item - 1, depth - 1),
    82              BottomUpTree(2 * item, depth - 1),
    83              item
    84          );
    85      else
    86          return NewTreeNode(NULL, NULL, item);
    87  } /* BottomUpTree() */
    88  
    89  
    90  void DeleteTree(treeNode* tree)
    91  {
    92      if (tree->left != NULL)
    93      {
    94          DeleteTree(tree->left);
    95          DeleteTree(tree->right);
    96      }
    97  
    98      free(tree);
    99  } /* DeleteTree() */
   100  
   101  
   102  int main(int argc, char* argv[])
   103  {
   104      unsigned   N, depth, minDepth, maxDepth, stretchDepth;
   105      treeNode   *stretchTree, *longLivedTree, *tempTree;
   106  
   107      N = atol(argv[1]);
   108  
   109      minDepth = 4;
   110  
   111      if ((minDepth + 2) > N)
   112          maxDepth = minDepth + 2;
   113      else
   114          maxDepth = N;
   115  
   116      stretchDepth = maxDepth + 1;
   117  
   118      stretchTree = BottomUpTree(0, stretchDepth);
   119      printf
   120      (
   121          "stretch tree of depth %u\t check: %li\n",
   122          stretchDepth,
   123          ItemCheck(stretchTree)
   124      );
   125  
   126      DeleteTree(stretchTree);
   127  
   128      longLivedTree = BottomUpTree(0, maxDepth);
   129  
   130      for (depth = minDepth; depth <= maxDepth; depth += 2)
   131      {
   132          long    i, iterations, check;
   133  
   134          iterations = pow(2, maxDepth - depth + minDepth);
   135  
   136          check = 0;
   137  
   138          for (i = 1; i <= iterations; i++)
   139          {
   140              tempTree = BottomUpTree(i, depth);
   141              check += ItemCheck(tempTree);
   142              DeleteTree(tempTree);
   143  
   144              tempTree = BottomUpTree(-i, depth);
   145              check += ItemCheck(tempTree);
   146              DeleteTree(tempTree);
   147          } /* for(i = 1...) */
   148  
   149          printf
   150          (
   151              "%li\t trees of depth %u\t check: %li\n",
   152              iterations * 2,
   153              depth,
   154              check
   155          );
   156      } /* for(depth = minDepth...) */
   157  
   158      printf
   159      (
   160          "long lived tree of depth %u\t check: %li\n",
   161          maxDepth,
   162          ItemCheck(longLivedTree)
   163      );
   164  
   165      return 0;
   166  } /* main() */