数据结构番外

数据结构番外—大根堆

文章目录

大根堆

大根堆

这一篇中我会给出一个基于C++模板实现的比较完善的heap类，你只需要简单地修改就可以把它变为小根堆

#include <iostream>
#include <vector>
#include <cmath>
using namespace std;template<typename T>
class heap
{// Big root heap
public:vector<T> data;size_t size;heap(){size = 0;}heap(vector<T> nums){// 99 5 36 7 22 17 46 12 2 19 25 28 1 92this->data = nums;this->size = nums.size() - 1;for (size_t i = size / 2; i >= 1; i--) {siftdown(i);}}void siftup(size_t i){bool check = false;if (i == 1) return;else {while (i != 1 && !check) {if (this->data[i] < this->data[i / 2]) {T temp = this->data[i / 2];this->data[i / 2] = this->data[i];this->data[i] = temp;i /= 2;}else check = true;}}return;}void siftdown(size_t i){bool check = false;size_t t = 0;while (i * 2 <= this->size && !check) {if (this->data[i] < this->data[i * 2]) {t = i * 2;}else t = i;if (i * 2 + 1 <= this->size) {if (this->data[t] < this->data[i * 2 + 1]) {t = i * 2 + 1;}}if (t != i) {T temp = this->data[t];this->data[t] = this->data[i];this->data[i] = temp;i = t;}else {check = true;}}return;}T deletemin(){T temp = this->data[1];this->data[1] = this->data[this->size--];siftdown(1);return temp;}void addElement(T num){this->data.push_back(num);this->size++;siftup(this->size);}void heap_sort(){heap<T> h_temp{ *this };while (h_temp.size >= 1) {cout << h_temp.deletemin() << " ";}cout << endl;}void heap_select(int m){if (m >= this->size-1) heap_sort();else {int cnt{ 0 };heap<T> h_temp{ *this };while (cnt < m) {printf("%d ", h_temp.deletemin());cnt++;}printf("\n");}}bool empty(){if (this->size == 0) return true;else return false;}template<typename U>friend ostream& operator<<(ostream& output, heap<U>& h){size_t n = 1;for (size_t i = 1; i <= h.size; i++) {output << h.data[i] << " ";if (i == n * 2 - 1) {output << endl;n *= 2;}}output << endl;return output;}
};