2018年南京工业大学828数据结构第十七题

#include <iostream>
#include <queue>
using namespace std;
typedef struct node
{
    int data;
    node *left;
    node *right;
} * BTREE;
int leftNum(BTREE root)
{
    queue<BTREE> q;
    int cnt = 0;
    while (!q.empty())
    {
        int size = q.size();
        for (int i = 0; i < size; i++)
        {
            BTREE tmp = q.front();
            q.pop();
            if (tmp->left == nullptr && tmp->right == nullptr)
            {
                cnt = cnt + 1;
            }
            if (tmp->left != nullptr)
            {
                q.push(tmp->left);
            }
            if (tmp->right != nullptr)
            {
                q.push(tmp->right);
            }
        }
    }
    return cnt;
}
int main()
{
    BTREE root = (BTREE)malloc(sizeof(node));
    int cnt = leftNum(root);
    cout << cnt << endl;
    return 0;
}