#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 2097152typedef 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);}