前两个为C++风格代码，后一个为C风格代码，除了输入输出，其它无差别，但C输入输出要比C++更快。
快速排序
1 #include <iostream>
2 using namespace std;
3
4 void swap(int num[], int i, int j)
5 {
6 int temp = num[i];
7 num[i] = num[j];
8 num[j] = temp;
9 }
10
11 int partition(int num[], int left, int right)
12 {
13 int key = left;
14 int value = num[key];
15 while (left < right)
16 {
17 while (left < right && num[right] >= value)right--;
18 while (left < right && num[left] <= value)left++;
19 swap(num, right, left);
20 }
21 swap(num, key, left);
22 return left;
23 }
24
25 void QuickSort(int num[], int begin, int end)
26 {
27 if (begin < end)
28 {
29 int middle = partition(num, begin, end);
30 QuickSort(num, begin, middle - 1);
31 QuickSort(num, middle + 1, end);
32 }
33 }
34
35 int main()
36 {
37 int num[100];
38 int n = 0;
39 while (cin >> n)
40 {
41 for (int i = 0; i < n; i++)
42 {
43 int temp = 0;
44 cin >> temp;
45 num[i] = temp;
46 }
47 QuickSort(num, 0, n - 1);
48 for (int i = 0; i < n; i++)
49 cout << num[i] << " ";
50 cout << endl;
51 }
52 return 0;
53 }
归并排序
1 #include <iostream>
2 using namespace std;
3
4 void Merge(int *from, int *to, int begin, int middle, int end)
5 {
6 int i = begin;
7 int j = middle + 1;
8 int k = i;
9 while (i <= middle && j <= end)
10 {
11 if (from[i] < from[j])
12 to[k++] = from[i++];
13 else to[k++] = from[j++];
14 }
15 while (i <= middle) to[k++] = from[i++];
16 while (j <= end) to[k++] = from[j++];
17 }
18
19 void MergePass(int *from, int *to, int end, int h)
20 {
21 int i = 0;
22 while (i <= end - 2 * h + 1)
23 {
24 Merge(from, to, i, i + h - 1, i + 2 * h - 1);
25 i += 2 * h;
26 }
27 if (i < end - h + 1)
28 Merge(from, to, i, i + h - 1, end);
29 else
30 for (int k = i; k <= end; k++)
31 {
32 to[k] = from[k];
33 }
34 }
35
36 void MergeSort(int *from, int *to, int begin, int end)
37 {
38 int h = 1;
39 while (h <= end)
40 {
41 MergePass(from, to, end, h);
42 h = 2 * h;
43 MergePass(to, from, end, h);
44 h = 2 * h;
45 }
46 }
47
48 int main() {
49 int num[100];
50 int num2[100];
51 int n = 0;
52 while (cin >> n)
53 {
54 for (int i = 0; i < n; i++)
55 {
56 int temp = 0;
57 cin >> temp;
58 num[i] = temp;
59 }
60 MergeSort(num, num2, 0, n - 1);
61 for (int i = 0; i < n; i++)
62 cout << num[i] << " ";
63 cout << endl;
64 }
65 return 0;
66 }
堆排序
1 #include <stdio.h>
2
3 void HeapAdjust(int *num, int s, int length)
4 {
5 int temp = num[s];
6 int child = 2 * s + 1;
7 while (child < length)
8 {
9 if (child + 1 < length && num[child] < num[child + 1])
10 child++;
11 if (num[s] < num[child])
12 {
13 num[s] = num[child];
14 num[child] = temp;
15 s = child;
16 child = 2 * s + 1;
17 }
18 else
19 break;
20 }
21 }
22
23 void buildingHeap(int *num, int length)
24 {
25 for (int i = (length - 1) / 2; i >= 0; --i)
26 HeapAdjust(num, i, length);
27 }
28
29 void HeapSort(int *num, int length)
30 {
31 buildingHeap(num, length);
32 for (int i = length - 1; i > 0; --i)
33 {
34 int temp = num[0];
35 num[0] = num[i];
36 num[i] = temp;
37 HeapAdjust(num, 0, i);
38 }
39 }
40
41 void print(int num[], int n) {
42 for (int i = 0; i < n; i++) {
43 printf("%d ", num[i]);
44 }
45 printf("\n");
46 }
47
48 int main()
49 {
50 int num[100];
51 int n = 0;
52 while (scanf("%d", &n) != EOF)
53 {
54 for (int i = 0; i < n; i++)
55 scanf("%d", &num[i]);
56 HeapSort(num, n);
57 print(num, n);
58 }
59 return 0;
60 }
验证OJ：https://www.nowcoder.com/practice/508f66c6c93d4191ab25151066cb50ef?tpId=69&&tqId=29657&rp=1&ru=/activity/oj&qru=/ta/hust-kaoyan/question-ranking
时间： 2024-10-11 07:12:58