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| #include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <string.h>
int linear_search(const int arr[], int size, int target) {
for (int i = 0; i < size; i++) {
if (arr[i] == target) {
return i;
}
}
return -1;
}
int binary_search(const int arr[], int size, int target) {
int left = 0, right = size - 1;
while (left <= right) {
int mid = left + (right - left) / 2;
if (arr[mid] == target) {
return mid;
} else if (arr[mid] < target) {
left = mid + 1;
} else {
right = mid - 1;
}
}
return -1;
}
void quick_sort(int arr[], int low, int high) {
if (low < high) {
int pivot = partition(arr, low, high);
quick_sort(arr, low, pivot - 1);
quick_sort(arr, pivot + 1, high);
}
}
int partition(int arr[], int low, int high) {
int pivot = arr[high];
int i = low - 1;
for (int j = low; j < high; j++) {
if (arr[j] <= pivot) {
i++;
swap(&arr[i], &arr[j]);
}
}
swap(&arr[i + 1], &arr[high]);
return i + 1;
}
void swap(int* a, int* b) {
int temp = *a;
*a = *b;
*b = temp;
}
void merge_sort(int arr[], int temp[], int left, int right) {
if (left < right) {
int mid = left + (right - left) / 2;
merge_sort(arr, temp, left, mid);
merge_sort(arr, temp, mid + 1, right);
merge(arr, temp, left, mid, right);
}
}
void merge(int arr[], int temp[], int left, int mid, int right) {
for (int i = left; i <= right; i++) {
temp[i] = arr[i];
}
int i = left, j = mid + 1, k = left;
while (i <= mid && j <= right) {
if (temp[i] <= temp[j]) {
arr[k++] = temp[i++];
} else {
arr[k++] = temp[j++];
}
}
while (i <= mid) {
arr[k++] = temp[i++];
}
while (j <= right) {
arr[k++] = temp[j++];
}
}
typedef struct {
int min;
int max;
double average;
int sum;
} ArrayStats;
ArrayStats calculate_stats(const int arr[], int size) {
ArrayStats stats = {arr[0], arr[0], 0.0, 0};
for (int i = 0; i < size; i++) {
if (arr[i] < stats.min) stats.min = arr[i];
if (arr[i] > stats.max) stats.max = arr[i];
stats.sum += arr[i];
}
stats.average = (double)stats.sum / size;
return stats;
}
void performance_test(void) {
printf("=== 数组算法性能测试 ===\n");
const int size = 100000;
int* arr = malloc(size * sizeof(int));
int* temp = malloc(size * sizeof(int));
if (arr == NULL || temp == NULL) {
printf("内存分配失败\n");
return;
}
srand((unsigned int)time(NULL));
for (int i = 0; i < size; i++) {
arr[i] = rand() % 10000;
}
clock_t start = clock();
int target = arr[size / 2];
int index = linear_search(arr, size, target);
clock_t end = clock();
printf("线性搜索: 找到索引 %d, 耗时 %.2f ms\n",
index, ((double)(end - start) / CLOCKS_PER_SEC) * 1000);
int* sorted_arr = malloc(size * sizeof(int));
memcpy(sorted_arr, arr, size * sizeof(int));
start = clock();
merge_sort(sorted_arr, temp, 0, size - 1);
end = clock();
printf("归并排序: 耗时 %.2f ms\n",
((double)(end - start) / CLOCKS_PER_SEC) * 1000);
start = clock();
index = binary_search(sorted_arr, size, target);
end = clock();
printf("二分搜索: 找到索引 %d, 耗时 %.2f ms\n",
index, ((double)(end - start) / CLOCKS_PER_SEC) * 1000);
ArrayStats stats = calculate_stats(arr, size);
printf("\n数组统计信息:\n");
printf("最小值: %d\n", stats.min);
printf("最大值: %d\n", stats.max);
printf("平均值: %.2f\n", stats.average);
printf("总和: %d\n", stats.sum);
free(arr);
free(temp);
free(sorted_arr);
}
int main(void) {
performance_test();
return 0;
}
|
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