PAT 05-树6 Path in a Heap

这次的作业完全是依葫芦画瓢，参照云课堂《数据结构》（http://mooc.study.163.com/learn/ZJU-1000033001#/learn/content）中何钦铭老师课件中有关建堆及插入的内容，再加上自己写的一个矬函数（竟然传了4个参数），OK了！题设要求及代码实现如下

/*
    Name: 
    Copyright: 
    Author: 
    Date: 05/04/15 19:34
    Description: 
Insert a sequence of given numbers into an initially empty min-heap H. Then for any given index i, you are supposed to print the path from H[i] to the root.

Input Specification:

Each input file contains one test case. For each case, the first line gives two positive integers N and M (<=1000) which are the size of the input sequence, and the number of indices to be checked, respectively. Given in the next line are the N integers in [-10000, 10000] which are supposed to be inserted into an initially empty min-heap. Finally in the last line, M indices are given.

Output Specification:

For each index i in the input, print in one line the numbers visited along the path from H[i] to the root of the heap. The numbers are separated by a space, and there must be no extra space at the end of the line.

Sample Input:
5 3
46 23 26 24 10
5 4 3
Sample Output:
24 23 10
46 23 10
26 10
*/

#include <stdio.h>
#include <stdlib.h>

#define MinData -10001

typedef struct HeapStruct
{
    int * Elements;
    int Size;
    int Capacity;
} * MinHeap;

MinHeap Create(int MaxSize);
void Insert(MinHeap H, int item);
void Print(MinHeap H, int * a, int N, int M);

int main()
{
//    freopen("in.txt", "r", stdin); // for test
    int N, M, i, item;
    MinHeap H;
    
    scanf("%d%d", &N, &M);
    
    H = Create(N);
    for(i = 0; i < N; i++)
    {
        scanf("%d", &item);
        Insert(H, item);
    }
    
    int a[M];
    
    for(i = 0; i < M; i++)
        scanf("%d", &a[i]);
        
    Print(H, a, N, M);
//    fclose(stdin); // for test
    return 0;
}

MinHeap Create(int MaxSize)
{
    MinHeap H = (MinHeap)malloc(sizeof(struct HeapStruct));
    H->Elements = (int *)malloc((MaxSize + 1) * sizeof(int));
    H->Size = 0;
    H->Capacity = MaxSize;
    H->Elements[0] = MinData;
    
    return H;
}

void Insert(MinHeap H, int item)
{
    int i;
    
    i = ++H->Size;
    for(; H->Elements[i / 2] > item; i /= 2)
        H->Elements[i] = H->Elements[i / 2];
    H->Elements[i] = item;
}

void Print(MinHeap H, int * a, int N, int M)
{
    int i;
    
    for(i = 0; i < M; i++)
    {
        if(a[i] <= N)
        {
            while(a[i])
            {
                printf("%d", H->Elements[a[i]]);
                if(a[i] > 1)
                    printf(" ");
                else
                    printf("\n");
                a[i] /= 2;
            }
        }
    }
}