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#include <vector>
#include <time.h>
#include <stdio.h>
#include <stdlib.h>
#include "kvec.h"
int main()
{
int M = 10, N = 20000000, i, j;
clock_t t;
t = clock();
for (i = 0; i < M; ++i) {
int *array = (int*)malloc(N * sizeof(int));
for (j = 0; j < N; ++j) array[j] = j;
free(array);
}
printf("C array, preallocated: %.3f sec\n",
(float)(clock() - t) / CLOCKS_PER_SEC);
t = clock();
for (i = 0; i < M; ++i) {
int *array = 0, max = 0;
for (j = 0; j < N; ++j) {
if (j == max) {
max = !max? 1 : max << 1;
array = (int*)realloc(array, sizeof(int)*max);
}
array[j] = j;
}
free(array);
}
printf("C array, dynamic: %.3f sec\n",
(float)(clock() - t) / CLOCKS_PER_SEC);
t = clock();
for (i = 0; i < M; ++i) {
kvec_t(int) array;
kv_init(array);
kv_resize(int, array, N);
for (j = 0; j < N; ++j) kv_a(int, array, j) = j;
kv_destroy(array);
}
printf("C vector, dynamic(kv_a): %.3f sec\n",
(float)(clock() - t) / CLOCKS_PER_SEC);
t = clock();
for (i = 0; i < M; ++i) {
kvec_t(int) array;
kv_init(array);
for (j = 0; j < N; ++j)
kv_push(int, array, j);
kv_destroy(array);
}
printf("C vector, dynamic(kv_push): %.3f sec\n",
(float)(clock() - t) / CLOCKS_PER_SEC);
t = clock();
for (i = 0; i < M; ++i) {
std::vector<int> array;
array.reserve(N);
for (j = 0; j < N; ++j) array[j] = j;
}
printf("C++ vector, preallocated: %.3f sec\n",
(float)(clock() - t) / CLOCKS_PER_SEC);
t = clock();
for (i = 0; i < M; ++i) {
std::vector<int> array;
for (j = 0; j < N; ++j) array.push_back(j);
}
printf("C++ vector, dynamic: %.3f sec\n",
(float)(clock() - t) / CLOCKS_PER_SEC);
return 0;
}
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