uva 548

题意：给你一个树的中序。后序遍历，让你找到前序遍历过程中，总和最大的一条路的叶节点的值。。。。。

#include <iostream>
#include <cstdio>
#include <cstring>
#include <vector>
using namespace std;
const int MAXN = 10005 ;

int inOrder[MAXN],postOrder[MAXN],nIndex;
class Node
{
    public:
        int data;
        Node *left;
        Node *right;
};
int nodeIndex;
Node node[MAXN];
vector<int>result;
vector<Node*>pResult;
bool flag;
int ans;

inline Node* NewNode()
{
    node[nodeIndex].left = NULL;
    node[nodeIndex].right = NULL;
    return &node[nodeIndex++];
}

inline void input()
{
    nIndex = 1 ;
    while (getchar() != '\n')
        scanf("%d",&inOrder[nIndex++]);
    for (int i = 0 ; i < nIndex ; i++)
        scanf("%d",&postOrder[i]);
}

Node* build(int *mid,int *post,int len)
{
    if (len == 0 )
        return NULL;
    int i = len - 1 ;
    while (post[len-1] != mid[i])
        i--;
    Node *h = NewNode();
    h->data = post[len-1];
    h->left = build(mid,post,i);
    h->right = build(mid+1+i,post+i,len-i-1);
    return h;
}

void dfs(Node *root ,int n)
{
	if(root->left == NULL && root->right == NULL)
	{
		result.push_back(n+root->data);
		pResult.push_back(root);
		return ;
	}
	if(root->left) dfs(root->left,n+root->data);
	if(root->right) dfs(root->right,n+root->data);
}

int main()
{
    while (scanf("%d",&inOrder[0]) != EOF)
    {
        input();
        nodeIndex = 0 ;
        Node *root = build(inOrder,postOrder,nIndex);
        result.clear();
        pResult.clear();
        dfs(root,0);
        int Min = 0 ;
        for (int i = 1 ; i < result.size() ; i++)
            if (result[i] < result[Min])
                Min = i ;
        printf("%d\n",pResult[Min]->data);
    }
    return 0;

}