数据结构常见的排序算法代码

冒泡排序

void bubble_sort(int arr[], int n) {
    for (int i = 0; i < n - 1; i++) {
        for (int j = 0; j < n - i - 1; j++) {
            if (arr[j] > arr[j + 1]) {
                int temp = arr[j];
                arr[j] = arr[j + 1];
                arr[j + 1] = temp;
            }
        }
    }
}

插入排序

void insert_sort(int arr[], int n) {
    for (int i = 1; i < n; i++) {
        int key = arr[i];
        int j = i - 1;
        while (j >= 0 && arr[j] > key) {
            arr[j + 1] = arr[j];
            j--;
        }
        arr[j + 1] = key;
    }
}

简单选择排序

void select_sort(int arr[], int n) {
    for (int i = 0; i < n - 1; i++) {
        int min = i;
        for (int j = i + 1; j < n; j++) {
            if (arr[j] < arr[min]) {
                min = j;
            }
        }
        int temp = arr[i];
        arr[i] = arr[min];
        arr[min] = temp;
    }
}

快速排序

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++;
            int temp = arr[i];
            arr[i] = arr[j];
            arr[j] = temp;
        }
    }
    int temp = arr[i + 1];
    arr[i + 1] = arr[high];
    arr[high] = temp;
    return i + 1;
}

归并排序

void merge_sort(int arr[], int low, int high) {
    if (low < high) {
        int mid = (low + high) / 2;
        merge_sort(arr, low, mid);
        merge_sort(arr, mid + 1, high);
        merge(arr, low, mid, high);
    }
}

void merge(int arr[], int low, int mid, int high) {
    int n1 = mid - low + 1;
    int n2 = high - mid;
    int L[n1], R[n2];
    for (int i = 0; i < n1; i++) {
        L[i] = arr[low + i];
    }
    for (int j = 0; j < n2; j++) {
        R[j] = arr[mid + 1 + j];
    }
    int i = 0, j = 0, k = low;
    while (i < n1 && j < n2) {
        if (L[i] <= R[j]) {
            arr[k] = L[i];
            i++;
        } else {
            arr[k] = R[j];
            j++;
        }
        k++;
    }
    while (i < n1) {
        arr[k] = L[i];
        i++;
        k++;
    }
    while (j < n2) {
        arr[k] = R[j];
        j++;
        k++;
    }
}

堆排序

void heapify(int arr[], int n, int i) {
    int largest = i;
    int l = 2 * i + 1; // 左子节点的索引
    int r = 2 * i + 2; // 右子节点的索引
 
    // 找出父节点、左子节点和右子节点中的最大值
    if (l < n && arr[l] > arr[largest])
        largest = l;
    if (r < n && arr[r] > arr[largest])
        largest = r;
 
    // 如果父节点不是最大值，则交换父节点和最大值，并递归进行堆维护
    if (largest != i) {
        swap(arr[i], arr[largest]);
        heapify(arr, n, largest);
    }
}
 
void heapSort(int arr[], int n) {
    // 构建最大堆
    for (int i = n / 2 - 1; i >= 0; i--)
        heapify(arr, n, i);
 
    // 排序
    for (int i = n - 1; i > 0; i--) {
        // 将堆的根元素与最后一个元素进行交换
        swap(arr[0], arr[i]);
 
        // 对新的堆进行维护，使其满足最大堆的定义
        heapify(arr, i, 0);
    }
}