C++ 堆排序
双鱼211 人气:0堆的实现
Heap.h 堆的管理及接口
#include<stdio.h> #include<stdlib.h> #include<assert.h> typedef int HPDataType; typedef struct Heap { HPDataType* a; int size; int capacity; }Heap; //堆的向下调整算法 void AdjustDown(HPDataType* a, int n, int root); //堆的向上调整算法 void AdjustUp(HPDataType* a, int child); //堆的初始化 void HeapInit(Heap* php, HPDataType* a,int n); //堆的销毁 void HeapDestroy(Heap* php); //堆的插入 void HeapPush(Heap* php, HPDataType x); //堆的删除 void HeapPop(Heap* php); //堆里的数据个数 int HeapSize(Heap* php); //判断堆是否为空 int HeapEmpty(Heap* php); //取堆顶数据 HPDataType HeapTop(Heap* php);
Heap.c 堆各个接口功能的实现
• 堆的插入:将x插入下标为size的位置,++size然后使用向上调整算法调整
• 堆的删除(删栈顶数据):将栈顶数据和下标为size-1位置的数据交换,然后–size,使用向下调整算法调整
#include "Heap.h" //堆向下调整算法 //建小堆 void AdjustDown(HPDataType* a, int n, int root) { int parent = root; int child = parent * 2 + 1; //孩子超过数组下标结束 while (child < n) { //child始终左右孩子中小的那个 if (a[child + 1] < a[child] && child + 1 <n)//防止没有右孩子 { ++child; } //小的往上浮,大的往下沉 if (a[child] < a[parent]) { int tem = a[parent]; a[parent] = a[child]; a[child] = tem; parent = child; child = parent * 2 + 1; } //中途child>parent则已满足小堆,直接break else { break; } } } //堆的向上调整算法 //建小堆 void AdjustUp(HPDataType* a, int child) { int parent = (child - 1) / 2; while (child > 0) { if (a[child] < a[parent]) { int tem = a[parent]; a[parent] = a[child]; a[child] = tem; child = parent; parent = (child - 1) / 2; } else { break; } } } //堆的初始化 void HeapInit(Heap* php, HPDataType* a, int n) { assert(php); assert(a); php->a = (HPDataType*)malloc(n * sizeof(HPDataType)); if (php->a == NULL) { printf("malloc fail\n"); exit(-1); } for (int i = 0; i < n; i++) { php->a[i] = a[i]; } //建堆 for (int i = (n - 2) / 2; i >= 0; --i) { AdjustDown(php->a, n, i); } php->capacity = n; php->size = n; } //堆的销毁 void HeapDestroy(Heap* php) { assert(php); free(php->a); php->a = NULL; php->capacity = 0; php->size = 0; } //堆的插入 void HeapPush(Heap* php, HPDataType x) { assert(php); if (php->size == php->capacity) { HPDataType* tem = (HPDataType*)realloc(php->a,php->capacity * 2 * sizeof(HPDataType)); if (tem == NULL) { printf("realloc fail\n"); exit(-1); } php->a = tem; php->capacity *= 2; } php->a[php->size] = x; ++php->size; AdjustUp(php->a,php->size - 1); } //堆的删除 void HeapPop(Heap* php) { assert(php); assert(php->size > 0); HPDataType tem = php->a[php->size - 1]; php->a[php->size - 1] = php->a[0]; php->a[0] = tem; --php->size; AdjustDown(php->a, php->size, 0); } //堆里的数据个数 int HeapSize(Heap* php) { assert(php); return php->size; } //判断堆是否为空 //为空返回1,不为空返回0 int HeapEmpty(Heap* php) { assert(php); return php->size == 0 ? 1 : 0; } //取堆顶数据 HPDataType HeapTop(Heap* php) { assert(php); assert(php->size > 0); return php->a[0]; }
test.c测试
#include "Heap.h" void TestHeap() { int arr[] = { 27, 28, 65, 25, 15, 34, 19, 49, 18, 37 }; Heap hp; HeapInit(&hp, arr, sizeof(arr)/sizeof(int)); while (!HeapEmpty(&hp)) { printf("%d ", HeapTop(&hp)); HeapPop(&hp); } printf("\n"); HeapDestroy(&hp); } int main() { TestHeap(); return 0; }
加载全部内容