AIZU 1001 Binary Tree Intersection And Union

本来很简单的题目，一开始是开数组去搞，果断地runtime error。因为最多有100个node，也就是说数组要开到2^100去，一开始脑子打结了~~晕~~

后来就用链表搞，晕，DFS1（）写错了，操，就写错一个参数~~

#include <iostream>
#include <stdio.h>
#include <string.h>
#include <math.h>
#include <stdlib.h>
#include <algorithm>
#include <vector>
#include <limits.h>
#include <queue>
#include <stack>
using namespace std;
struct treenode
{
    treenode *l,*r;
    treenode(){l = NULL;r =NULL;}
};
stack <treenode*> S;
string getans(treenode* p)
{
    if(p == NULL) return "";
    else return "("+getans(p->l)+","+getans(p->r)+")";
}
void DFS1(treenode *root,treenode *root1,treenode *root2)
{
    //cout<<l++<<endl;
    if(root1->l!=NULL&&root2->l!=NULL)
    {
        treenode *node = new treenode;
        root ->l = node;
        DFS1(root->l,root1->l,root2->l);
    }
    if(root1->r!=NULL&&root2->r!=NULL)
    {
        treenode *node = new treenode;
        root ->r = node;
        DFS1(root->r,root1->r,root2->r);
    }

}
void DFS2(treenode *root,treenode* root1)
{
    if(root1->l!=NULL)
    {
        if(root->l==NULL){
        treenode *node = new treenode;
        root ->l = node;}
        DFS2(root->l,root1->l);
    }
    if(root1->r!=NULL)
    {
        if(root->r==NULL){
        treenode *node = new treenode;
        root->r = node;}
        DFS2(root->r,root1->r);
    }
}
int main()
{
    int i,j;
    char op[2],tree1[10000],tree2[10000];

    while(scanf("%s%s%s",&op,&tree1,&tree2)!=EOF)
    {
        int len1 = strlen(tree1);
        int len2 = strlen(tree2);
        //int cur;
        treenode *root1 = new treenode;
        for(i = 0;i < len1;i ++)
        {
            //cout<<tree1[i]<<endl;
            if(tree1[i]=='(')
            {
                if(i == 0)
                {
                    S.push(root1);
                }
                else
                {
                    if(tree1[i-1] == '(')
                    {
                       treenode* tmp = S.top();
                       treenode* node = new treenode;
                       S.push(node);
                       tmp ->l = node;
                    }
                    else
                    {
                        treenode* tmp = S.top();
                        treenode* node = new treenode;
                        S.push(node);
                        tmp->r = node;
                    }
                }
            }
            else if(tree1[i] == ')') S.pop();
        }
        //cout<<"dsa"<<endl;
        treenode *root2 = new treenode;
        for(i = 0;i < len2;i ++)
        {
            if(tree2[i]=='(')
            {
                if(i == 0)
                {
                    S.push(root2);
                }
                else
                {
                    if(tree2[i-1] == '(')
                    {
                       treenode* tmp = S.top();
                       treenode* node = new treenode;
                       S.push(node);
                       tmp ->l = node;
                    }
                    else
                    {
                        treenode* tmp = S.top();
                        treenode* node = new treenode;
                        S.push(node);
                        tmp->r = node;
                    }
                }
            }
            else if(tree2[i] == ')') S.pop();
        }
        //cout<<"sda"<<endl;
        if(op[0]=='i')
        {
            treenode *root = new treenode;
            DFS1(root,root1,root2);
            //cout<<"das"<<endl;
            string ans = getans(root);
            cout<<ans<<endl;
        }
        else
        {
            treenode *root = new treenode;
            DFS2(root,root1);
            DFS2(root,root2);
            string ans = getans(root);
            cout<<ans<<endl;
        }
    }

}