BUAA 2014级数据结构第五次上机 二叉树之数组转换广义表

按题意建立好二叉树，再按照先序遍历输出结果。

#include<cstdio>
#include<vector>
#include<queue>
#include<string.h>
#include<algorithm>
using namespace std;
 
struct node
{
    int left, right, date;
 
}node[];
 
int a[], flag[];
 
void dfs(int father)
{
    printf("%d", node[father].date);
    if (node[father].left != - || node[father].right != -) printf("(");
    if (node[father].left != - && node[father].right == -)
    {
        dfs(node[father].left);
        printf(")");
    }
    else if (node[father].left == - && node[father].right != -)
    {
        printf(",");
        dfs(node[father].right);
        printf(")");
    }
    else if (node[father].left != - && node[father].right != -)
    {
        dfs(node[father].left);
        printf(",");
        dfs(node[father].right);
        printf(")");
    }
 
}
 
int main()
{
    int n, i;
    while (~scanf("%d", &n))
    {
        int numm = ;
        for (i = ; i <= ; i++)
        {
            node[i].date = -;
            node[i].left = -;
            node[i].right = -;
        }
        memset(flag, , sizeof(flag));
        for (i = ; i <= n; i++) scanf("%d", &a[i]);
        int father = , jishu = ;
        node[numm].date = a[]; numm++;
        for (i = ; i <= n; i++)
        {
            if (jishu == )
            {
                jishu++;
                if (a[i] != -)
                {
                    node[father].left = numm;
                    node[numm].date = a[i];
                    numm++;
                }
            }
            else if (jishu == )
            {
                if (a[i] != -)
                {
                    node[father].right = numm;
                    node[numm].date = a[i];
                    numm++;
                }
                jishu = ;
                father++;
            }
        }
        dfs();
        printf("\n");
    }
    return ;
}