二叉树基本操作实现（二叉树的顺序存储）

#include <iostream>
using namespace std;

typedef struct  
{
    int data[100];
    int length;
}bintree;

void init_tree(bintree *ptree, int *input, int len)
{
    int i;
    for(i = 0; i < 100; ++i)
    {
        if(i < len)
            ptree->data[i] = input[i];
        else
            ptree->data[i] = -1;
    }
    ptree->length = len;
    return ;
}
int find_lson(bintree *ptree, int x)
{
    int i = 0;
    while(ptree->data[i] != x && i < ptree->length)
    {
        ++i;
    }
    if(i >= ptree->length)
    {
        cout << "can not find!!!"<< endl;
        return -1;
    }
    return 2 * i + 1;
}

int find_rson(bintree *ptree, int x)
{
    int i = 0;
    while(ptree->data[i] != x && i < ptree->length)
    {
        ++i;
    }
    if(i >= ptree->length)
    {
        cout << "can not find!!!" << endl;
        return -1;
    }
    return 2 * i + 2;
}

int is_empty(bintree *ptree)
{
    return ptree->length == 0 ? 1 : 0;
}

void forward_traverse(bintree *ptree, int i)
{
    if(ptree->data[i] == -1)
        return ;
    else
    {
        //cout << ptree->data[i] << "\t";
        forward_traverse(ptree, i * 2 + 1);
        forward_traverse(ptree, i * 2 + 2);cout << ptree->data[i] << "\t";
    }
}

int main()
{
    bintree *ptree = (bintree *)malloc(sizeof(bintree));
    int input[] = {1,2,3,4,5};
    int len = sizeof(input)/sizeof(int);
    init_tree(ptree, input, len);
    cout << "find lson: " << ptree->data[find_rson(ptree, 2)] << endl; 
    cout << "is empty " << is_empty(ptree) << endl;
    forward_traverse(ptree, 0);
    return 0;
}