c_cpp/lib/klib/test/kvec_test.cc

   1 #include <vector>
   2 #include <time.h>
   3 #include <stdio.h>
   4 #include <stdlib.h>
   5 #include "kvec.h"
   6
   7 int main()
   8 {
   9         int M = 10, N = 20000000, i, j;
  10         clock_t t;
  11         t = clock();
  12         for (i = 0; i < M; ++i) {
  13                 int *array = (int*)malloc(N * sizeof(int));
  14                 for (j = 0; j < N; ++j) array[j] = j;
  15                 free(array);
  16         }
  17         printf("C array, preallocated: %.3f sec\n",
  18                    (float)(clock() - t) / CLOCKS_PER_SEC);
  19         t = clock();
  20         for (i = 0; i < M; ++i) {
  21                 int *array = 0, max = 0;
  22                 for (j = 0; j < N; ++j) {
  23                         if (j == max) {
  24                                 max = !max? 1 : max << 1;
  25                                 array = (int*)realloc(array, sizeof(int)*max);
  26                         }
  27                         array[j] = j;
  28                 }
  29                 free(array);
  30         }
  31         printf("C array, dynamic: %.3f sec\n",
  32                    (float)(clock() - t) / CLOCKS_PER_SEC);
  33         t = clock();
  34         for (i = 0; i < M; ++i) {
  35                 kvec_t(int) array;
  36                 kv_init(array);
  37                 kv_resize(int, array, N);
  38                 for (j = 0; j < N; ++j) kv_a(int, array, j) = j;
  39                 kv_destroy(array);
  40         }
  41         printf("C vector, dynamic(kv_a): %.3f sec\n",
  42                    (float)(clock() - t) / CLOCKS_PER_SEC);
  43         t = clock();
  44         for (i = 0; i < M; ++i) {
  45                 kvec_t(int) array;
  46                 kv_init(array);
  47                 for (j = 0; j < N; ++j)
  48                         kv_push(int, array, j);
  49                 kv_destroy(array);
  50         }
  51         printf("C vector, dynamic(kv_push): %.3f sec\n",
  52                    (float)(clock() - t) / CLOCKS_PER_SEC);
  53         t = clock();
  54         for (i = 0; i < M; ++i) {
  55                 std::vector<int> array;
  56                 array.reserve(N);
  57                 for (j = 0; j < N; ++j) array[j] = j;
  58         }
  59         printf("C++ vector, preallocated: %.3f sec\n",
  60                    (float)(clock() - t) / CLOCKS_PER_SEC);
  61         t = clock();
  62         for (i = 0; i < M; ++i) {
  63                 std::vector<int> array;
  64                 for (j = 0; j < N; ++j) array.push_back(j);
  65         }
  66         printf("C++ vector, dynamic: %.3f sec\n",
  67                    (float)(clock() - t) / CLOCKS_PER_SEC);
  68         return 0;
  69 }