排序算法

一、冒泡排序

#include <stdio.h>void bubbleSort(int a[], int n);void bubbleSort(int a[], int n) {    int i, j;    bool swap = true;//如果序列已经排好序，则跳出循环    while(swap) {        swap = false;        for(i = 0; i < n-1; i++) {//只需要进行n-1次交换            for(j = 0; j < n-1-i; j++) {//一次交换完成后，次数便减少一次                if(a[j] > a[j+1]) {                    int t = a[j];                    a[j] = a[j+1];                    a[j+1] = t;                    swap = true;                }            }        }    }}int main() {    int a[] = {1,2,5,4,6,8,9,7,3};    int i;    bubbleSort(a, 9);    for(i = 0; i < 9; i++) {        printf("%d ", a[i]);    }    printf("\n");    return 0;}

二、插入排序

#include <stdio.h>void insertSort(int a[], int n);void insertSort(int a[], int n) {    int i;    for(i = 1; i < n; i++) {//从第二个开始插入，第一个默认为排序完成的元素        int get = a[i]; //类似于打牌，a[i]为摸到的牌，将其插入到手中已经排好序的牌        int j = i-1;//j表示手中的牌的下标，从最后一张开始        while(j >= 0 && a[j] >= get) {//找到get插入的位置，该循环结束后j为get插入的前面的位置            a[j+1] = a[j];            j--;        }        a[j+1] = get;    }}int main() {    int a[] = {1,2,5,4,6,8,9,7,3};    int i;    insertSort(a, 9);    for(i = 0; i < 9; i++) {        printf("%d ", a[i]);    }    printf("\n");    return 0;}

三、选择排序

#include <stdio.h>void selectSort(int a[], int n);void selectSort(int a[], int n) {    int i, j ,minIndex;    for(i = 0; i < n-1; i++) {        minIndex = i;//假设第i个就是最小的        for(j = i+1; j < n; j++) {//找到最小的元素下标minIndex            if(a[minIndex] > a[j]) {                minIndex = j;            }        }        if(minIndex != i) {        //如果i!=minIndex说明i不是最小元素的下标，将找到的a[minIndex]与其交换            int t = a[minIndex];            a[minIndex] = a[i];            a[i] = t;        }    }}int main() {    int a[] = {1,2,5,4,6,8,9,7,3};    int i;    selectSort(a, 9);    for(i = 0; i < 9; i++) {        printf("%d ", a[i]);    }    printf("\n");    return 0;}

四、快速排序

#include <stdio.h>void quickSort(int a[], int n);void quickSort(int a[], int start, int end) {    if(start >= end) return;    int i = start, j = end, p = a[start];    while(i < j) {        while(i < j && a[j] >= p)            j--;        while(i < j && a[i] <= p)            i++;        if(i < j) {             int t = a[i];            a[i] = a[j];            a[j] = t;        }    }    a[start] = a[i];    a[i] = p;    quickSort(a, start, i-1);    quickSort(a, i+1, end);}int main() {    int arr[] = {0,3,5,6,8,9,7,4,2,1};    int i;    int n = sizeof(arr)/sizeof(arr[0]);    quickSort(arr, 0, n-1);    for(i = 0; i < n; i++) {        printf("%d ", arr[i]);    }    printf("\n");    return 0;}

五、希尔排序

#include <stdio.h>void shellSort(int a[], int count);void insert(int a[], int count, int start, int step);void insert(int a[], int count, int start, int step) {    int i, j, k;    for(i = start+step; i < count; i += step) {        int get = a[i];        for(j = start; j < i && a[j] <= get; j += step){;}        for(k = i; k > j; k -= step) {            a[k] = a[k-step];        }        a[j] = get;    }}void shellSort(int a[], int count) {    int step, start;    for(step = count/2; step > 0; step /= 2) {        for(start = 0; start < step; start++) {            insert(a, count, start, step);        }    }}int main() {    int arr[] = {0,3,5,6,8,9,7,4,2,1};    int i;    int n = sizeof(arr)/sizeof(arr[0]);    shellSort(arr, n);    for(i = 0; i < n; i++) {        printf("%d ", arr[i]);    }    printf("\n");    return 0;}

六、堆排序

#include <stdio.h>void heapSort(int *data, int count);void adjustBigHeap(int *data, int count, int root);void swap(int *one, int *another);void swap(int *one, int *another) {    int t = *one;    *one = *another;    *another = t;}void adjustBigHeap(int *data, int count, int root) {    int leftChild;    int rightChild;    int child;    while(root <= count/2-1) {//非叶子节点        leftChild = 2*root+1;        rightChild = 2*root +2;        child = rightChild >= count             ? leftChild             : (data[leftChild] > data[rightChild] ? leftChild : rightChild);        if(data[root] >= data[child]) {            return;        }        swap(data+root, data+child);        root = child;    }}void heapSort(int *data, int count) {    int root;    for(root = count/2-1; root >= 0; root--) {        adjustBigHeap(data, count, root);    }    do {        swap(data, data+count-1);        adjustBigHeap(data, --count, 0);    }while(count > 1);}int main() {    int arr[] = {0,3,5,6,8,9,7,4,2,1};    int i;    int n = sizeof(arr)/sizeof(arr[0]);    heapSort(arr, n);    for(i = 0; i < n; i++) {        printf("%d ", arr[i]);    }    printf("\n");    return 0;}