HDU 1561 The more, The Better (树形DP)

http://acm.hdu.edu.cn/showproblem.php?pid=1561

数组开小了越界，查了好久才查出来。。。GCC太能容忍错误了。。。坑！！！

题意：

给你一棵树，选中某一个节点花费1，得到它的价值，而且必须选中父节点才能选中子节点，问：在花费m下，最大价值为多少？

最基本的树形DP，和前面的几道题一样

dp[s][k]表示选中s节点，总花费k时的最大价值

状态转移：

for (int k = m; k >= 2; k--)
            for (int j = 1; j < k; j++)
                dp[s][k] = max(dp[s][k], dp[s][k - j] + dp[v][j]);

#pragma comment(linker, "/STACK:102400000,102400000")
#include <cstdio>
#include <iostream>
#include <cstring>
#include <string>
#include <cmath>
#include <set>
#include <list>
#include <map>
#include <iterator>
#include <cstdlib>
#include <vector>
#include <queue>
#include <stack>
#include <algorithm>
#include <functional>
using namespace std;
typedef long long LL;
#define ROUND(x) round(x)
#define FLOOR(x) floor(x)
#define CEIL(x) ceil(x)
const int maxn = 210;
const int maxm = 410;
const int inf = 0x3f3f3f3f;
const LL inf64 = 0x3f3f3f3f3f3f3f3fLL;
const double INF = 1e30;
const double eps = 1e-6;
const int P[4] = {0, 0, -1, 1};
const int Q[4] = {1, -1, 0, 0};
const int PP[8] = { -1, -1, -1, 0, 0, 1, 1, 1};
const int QQ[8] = { -1, 0, 1, -1, 1, -1, 0, 1};

int n, m;
int dp[maxn][maxn];
struct Edge
{
    int u, v;
    int next;
} edge[maxm];
int en;
int head[maxn];
bool vis[maxn];
int node[maxn];
void addsubedge(int u, int v)
{
    edge[en].u = u;
    edge[en].v = v;
    edge[en].next = head[u];
    head[u] = en++;
}
void addedge(int u, int v)
{
    addsubedge(u, v);
    //addsubedge(v, u);
}
void init()
{
    memset(head, -1, sizeof(head));
    memset(dp, 0, sizeof(dp));
    en = 0;
    memset(node, 0, sizeof(node));
}
void input()
{
    int u, w;
    for (int i = 1; i <= n; i++)
    {
        scanf("%d%d", &u, &w);
        node[i] = w;
        addedge(u, i);
    }
}
void dfs(int s)
{
    //vis[s] = 1;
    dp[s][1] = node[s];
    // cout << "dfs s: " << s << endl;
    //cout<<"dp[s][1]: "<<s<<" "<<dp[s][1]<<endl;
    for (int i = head[s]; i != -1; i = edge[i].next)
    {
        int v = edge[i].v;
        //if (!vis[v]) dfs(v);
        dfs(v);
        for (int k = m; k >= 2; k--)
            for (int j = 1; j < k; j++)
                dp[s][k] = max(dp[s][k], dp[s][k - j] + dp[v][j]);
    }
}
void debug()
{
    for (int i = 0; i <= n; i++) cout << head[i] << " ";
    cout << endl;
    for (int i = 0; i <= n; i++)
    {
        for (int j = 0; j <= m; j++) cout << dp[i][j] << '	';
        cout << endl;
    }
}
void solve()
{
    node[0] = 0;
    dfs(0);
}
void output()
{
    printf("%d
", dp[0][m]);
}
int main()
{
    // std::ios_base::sync_with_stdio(false);
#ifndef ONLINE_JUDGE
    freopen("in.cpp", "r", stdin);
#endif

    while (~scanf("%d%d", &n, &m))
    {
        if (!n && !m) return 0;
        m++;
        init();
        input();
        solve();
        // debug();
        output();
    }
    return 0;
}