各种排序算法

年代有些久远了，但平时排序算法用得很多，所以汇总一下

各排序算法复杂度和稳定性的比较

C或c++实现

直接插入

void insert(int vector[],int n) {                     // 直接插入算法           int i, j, t;    for (i=1; i<n; i++) {                  t=vector[i];                   for(j=i-1; j>=0 && t<vector[j]; j--) {                            vector[j+1] = vector[j];                   }                  vector[j+1] = t;    }}

直接选择

Void select(int a[], int n) {                    // 直接选择算法    int i, j;    for(i = 0; i < n-1; i++) {        k=i;        for (j = i+1; j < n; j++)  if(a[k] > a[j])  k = j;        if(i != k) swap(a[k], a[i]);    }}

冒泡排序

void bubble_sort(int a[],int n) {                // 冒泡排序算法：   int i, j;   for (i = 0; i < n-1; i++) {       for (j = 0; j < n-1-i; j++)           if (a[j] > a[j+1]) swap(a[j], a[j+1])   }}

shell排序

// Shell 排序void shellSort(int array[], int length)  {       int p, i, j, t;    for (p = length/2; p > 0; p /= 2) {          for (i = p; i < length; i++) {             for(j = i-p; j >= 0 && array[j] > array[j+p]; j -= p) {                  t = array[j]; array[j] = array[j+p]; array[j+p] = t;            }        }      }}

快速排序

void sort(int*a, int i, int j) {int left, right, mid, t;left = i; right = j;mid = a[(i+j)/2];do {while (a[left] < mid) left++;while (a[right] > mid) right--;if (left <= right) {t = a[left]; a[left] = a[right]; a[right] = t;left++; right--;}} while (left <= right);if (left < j) sort(a, left, j);if (right > i) sort(a, i, right);}

堆排序

#include<iostream>using namespace std;void Swap(int &a, int &b) {int t = a;a = b;b = t;}void HeapAdjust(int s[], int start, int num) { // 调整为最大堆 int i, j;while (2*start+1 < num) {j = 2*start+1;if (j+1 < num && s[j] < s[j+1]) j++;  // 选择左右子树中的较大者与父节点交换if (s[start] < s[j]) {Swap(s[start], s[j]);start = j;  // 反复筛选 }else break; }} void HeapSort(int s[], int n) {int i, j;for (i = n/2-1; i >= 0; i--) HeapAdjust(s, i, n);  // 初始化最大堆for (j = n-1; j >= 0; j--) {Swap(s[0], s[j]);  // 通过交换堆顶元素与堆底元素达到取堆顶最大元素的目的 HeapAdjust(s, 0, j); // 对剩余j-1元素重新建成堆调整} }int main() {int a[12] = { 8, 2, 5, 43, 54, 1, 88, 23, 15, 99, 24, 33 };HeapSort(a, 12);for (int p = 0; p < 12; p++) cout << a[p] << " ";cout << endl;system("pause");return 0;}

归并排序

无递归：

#include<iostream>#include<cstdio>using namespace std;void MergeStep(int a[], int r[], int s, int m, int n) {int i = s, k = s, j = m+1;while (i <= m &&j <= n) {if (a[i] <= a[j]) r[k++] = a[i++];else r[k++] = a[j++];}while (i <= m) r[k++] = a[i++];while (j <= n) r[k++] = a[j++];}void MergePass(int a[], int r[], int n, int len) {int s = 0, e;while (s + len < n) {e = s + 2 * len - 1;if (e >= n) e = n - 1;MergeStep(a, r, s, s + len - 1, e);s = e + 1;}if (s < n) {for (; s < n; s++) r[s] = a[s];}}void MergeSort(int a[], int n) {int *p;int len = 1, f = 0;p = (int*)malloc(sizeof(int)*n);while (len < n) {if (f) MergePass(p, a, n, len);else MergePass(a, p, n, len);len *= 2;f = 1 - f;}if (f) {for (f = 0; f < n; f++) a[f] = p[f];}free(p);}int main() {int a[12] = { 8, 2, 5, 43, 54, 1, 88, 23, 15, 99, 24, 33 };MergeSort(a, 12);for (int p = 0; p < 12; p++) cout << a[p] << " ";cout << endl;system("pause");return 0;}

有递归：

void Merge(int a[], int low, int m, int high) {// low为第1有序区的首元素， m为第1有序区的末元素 int *b = new int[high-low+1];if (!b) {cout << "ERROR!" << endl;return; }int i = low, k = 0, j = m+1;  // j（m+1）为第2有序区的首元素 while (i <= m && j <= high) {if (a[i] <= a[j]) b[k++] = a[i++];else b[k++] = a[j++];}while (i <= m) b[k++] = a[i++];while (j <= high) b[k++] = a[j++];for(i=low, k=0; i <= high; i++, k++) a[i]=b[k]; // //将排好序的存回数组a中low到high这区间 delete []b;}void Msort(int a[], int s, int t) {int m = (s+t) /2;if (s < t) {Msort(a, s, m); // 左边 Msort(a, m+1, t); // 右边 Merge(a, s, m, t);}}