Insert an element into a min heap (No sentinel)———插入无哨兵的最小堆（PTA）

题目描述：

The program below contains a function?insertIntoHeap( )?which inserts an element into a min heap/priority queue(最小堆).

Fill in the blanks to complete the function.

完整题解：

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

//堆是一种特殊的树（1，完全二叉树且每个节点都必须大于等于/小于等于其子树中每个节点的值）

/* Definition of Heap struct  */
struct Heap{
    int *data;   // 堆元素存储空间指针，堆元素按照二叉树顺序存储的方式，
    //从data[1]开始存放，data[0]不使用，无哨兵元素
    int capacity; // capacity(容量) of heap
    int size;  // number of heap elements
};
struct Heap* initHeap(int capacity){   // 初始化这个Heap
    struct Heap* h;
    h = (struct Heap*)malloc(sizeof(struct Heap));
    if(!h) return NULL;
    h->data = (int*)malloc(sizeof(int)*capacity+1);
    if(h->data == NULL){
        free(h);
        return NULL;
    }
    h->capacity = capacity;
    h->size = 0;
    return h;
};
int insertIntoHeap(struct Heap* h, int x){
    if( h->size==h->capacity) return 0;  
    //  returns 0 if heap is full. （There is NO fuction like the name "IsFull( )")
    int i;
    for(i=++h->size; i>1&& x<h->data[i/2]; i/=2)
        h->data[i] = h->data[i/2];
    h->data[i] = x;
    return 1;  // success
}
void printHeap(struct Heap* h) {
    printf("Heap elements:\n");
    for (int i = 1; i <= h->size; i++) {
        printf("%d ", h->data[i]);
    }
    printf("\n");
}
int main(){  /* main仅为示例，实际使用以上代码中两个函数的情况可能有所不同 */
    struct Heap *h;
    h = initHeap( 5 );
    insertIntoHeap(h,  1);
    insertIntoHeap(h,  10);
    insertIntoHeap(h,  3);
    insertIntoHeap(h,  4);
    insertIntoHeap(h,  5);
    printHeap(h);
    return 0;
}

经过实际运行后所填空能够正常运行。