1 /**
2 * 排序算法之归并排序
3 */
4 #include <iostream>
5 #include <vector>
6 using namespace std;
7
8 void mergeKP(vector<int>& vec, int l1, int r1, int l2, int r2) {
9 int i = l1;
10 int j = l2;
11 int n = (r1 - l1 + 1) + (r2 - l2 + 1);
12
13 vector<int> temp(n);
14 int k = 0;
15 while (i <= r1 && j <= r2) {
16 if (vec[i] < vec[j]) {
17 temp[k++] = vec[i++];
18 } else {
19 temp[k++] = vec[j++];
20 }
21 }
22 while (i <= r1) {
23 temp[k++] = vec[i++];
24 }
25 while (j <= r2) {
26 temp[k++] = vec[j++];
27 }
28 for (int i = 0; i < n; i++) {
29 vec[l1 + i] = temp[i];
30 }
31 }
32
33 void sortGuiBing(vector<int>& vec,int start, int end) {
34 if (start < end) {
35 int mid = (start + end) / 2;
36 sortGuiBing(vec, start, mid);
37 sortGuiBing(vec, mid + 1, end);
38 mergeKP(vec, start, mid, mid + 1, end);
39 }
40 }
41 int main() {
42 vector<int> vec = {2,1,3,5,4};
43 int len = vec.size();
44 sortGuiBing(vec, 0, len - 1);
45 for (int i = 0; i < len; ++i) {
46 cout << vec[i] << endl;
47 }
48 return 0;
49 }
