POJ1192 最优连通子集

#include<iostream>
#include<cstdio>
#include<vector>
#include<cstring>
#include<cmath>
using namespace std;
#define pb push_back
#define mp make_pair
#define se second
#define fs first
#define ll long long
#define CLR(x) memset(x,0,sizeof x)
#define MC(x,y) memcpy(x,y,sizeof(x))  
#define SZ(x) ((int)(x).size())
#define FOR(it,c) for(__typeof((c).begin()) it=(c).begin();it!=(c).end();it++)
#define lson l,m,rt<<1
#define rson m+1,r,rt<<1|1 
#define INF 2097152
typedef pair<int,int> P;
const double eps=1e-9;
const int maxn=1010;
const int mod=1e9+7;

struct Node{
    int x,y,v;
};

Node p[maxn];

int dp[maxn],Fa[maxn];
vector<int> Edge[maxn];
vector<int> v; 

void dfs(int u,int fa){
    v.pb(u);
    Fa[u]=fa;
    for(int i=0;i<Edge[u].size();i++){
        if(Edge[u][i]!=fa) dfs(Edge[u][i],u); 
    }
}


int main(){
    int n;
    scanf("%d",&n);
    for(int i=1;i<=n;i++)  scanf("%d%d%d",&p[i].x,&p[i].y,&p[i].v);
    for(int i=1;i<=n;i++)
    for(int j=i+1;j<=n;j++){
        if(abs(p[i].x-p[j].x)+abs(p[i].y-p[j].y)==1){
            Edge[i].pb(j);
            Edge[j].pb(i);
        }
    }
    int tmp=0;
    dfs(1,-1);
    for(int i=v.size()-1;i>=0;i--){
        int k=v[i];
        dp[k]=p[k].v;
        for(int j=0;j<Edge[k].size();j++) if(Edge[k][j]!=Fa[k]){
            dp[k]=max(dp[k],dp[k]+dp[Edge[k][j]]);
        }
        tmp=max(tmp,dp[k]);
    }
    printf("%d\n",tmp);
}