//CLOCKS_PER_SEC
using namespace std;
#include<bits/stdc++.h>
#define sqr(x) 1ll*(x)*(x)
//#define sort stable_sort
#define ll long long
#define mk make_pair
#define pb push_back
#define in insert
#define mtr(x,y,z) mk(mk(x,y),z)
#define fi first
#define se second
#define lch(x) ((x)<<1)
#define rch(x) (((x)<<1)|1)
#define all(x) (x).begin(),(x).end()
#define titose CLOCKS_PER_SEC
#define fpi(x) freopen(x,"r",stdin);
#define fpo(x) freopen(x,"w",stdout);
#define fprio fpi("in.txt");fpo("out.txt");
#define fast ios_base::sync_with_stdio(false);
inline void read(int &x){int v=0,f=1;char c=getchar();while (!isdigit(c)&&c!='-') c=getchar();if (c=='-') f=-1; else v=(c&15);while (isdigit(c=getchar())) v=(v<<1)+(v<<3)+(c&15);x=v*f;}
inline void read(ll &x){ll v=0ll,f=1ll;char c=getchar();while (!isdigit(c)&&c!='-') c=getchar();if (c=='-') f=-1; else v=(c&15);while (isdigit(c=getchar())) v=(v<<1)+(v<<3)+(c&15);x=v*f;}
inline void readc(char &x){char c;while (((c=getchar())==' ')||c=='\n');x=c;}
#define pii pair<int,int>
#define pll pair<ll,ll>
#define vi vector<int>
#define vl vector<ll>
#define si set<int>
//#define sl set<ll>
#define mii map<int,int>
#define mll map<ll,ll>
#define msi map<string,int>
#define msl map<string,ll>
#define piii pair<int,pii >
#define piipi pair<pii,int>
#define plll pair<ll,pll >
#define pllpl pair<pll,ll>
#define pqi priority_queue<int>
#define pql priority_queue<ll>
#define npqi priority_queue<int,vector<int>,greater<int> >
#define npql priority_queue<ll,vector<ll>,greater<ll> >
#define forup(i,a,b) for ((i)=(a);(i)<=(b);(i)++)
#define fordo(i,a,b) for ((i)=(a);(i)>=(b);(i)--)
#define rep(i,x) forup ((i),1,(x))
#define repd(i,x) fordo ((i),(x),1)
#define rep0(i,x) forup ((i),0,((int)(x))-1)
#define rep0d(i,x) fordo ((i),((int)(x))-1,0)
#define itr iterator
#define fe(itcalc,c) for(__typeof((c).begin()) itcalc=(c).begin();itcalc!=(c).end();itcalc++)
#define NO {cout<<"NO";return 0;}
#define YES {cout<<"YES";return 0;}
#define y0 y000000000000000000000000000
#define y1 y111111111111111111111111111
#define j0 j000000000000000000000000000
#define j1 j111111111111111111111111111
#define cl0(a) memset((a),(0),(sizeof((a))))
#define clz(a) memset((a),(0x16),(sizeof((a))))
#define clf(a) memset((a),(-(0x16)),(sizeof((a))))
#define inf 0x3bbbbbbb
#define lnf 0x2bbbbbbbbbbbbbbbll
//#define sqrt divi
#define p2(i) (1ll<<(i))
#define readi read
#define readll read
/*************************************************/
int n,m,i,j,s=0,t=2001,px[1005],py[1005],dis[2005],inq[2005];
map<pair<int,int>,int> mp;
struct edg
{
	int y;ll z;
}ee[1000005];
vector<int> e[2005];int tot;
ll sum;
void add(int x,int y,ll z)
{
//	cerr<<x<<' '<<y<<' '<<z<<endl;
	tot++;
	e[x].pb(tot+tot-2);e[y].pb(tot+tot-1);
	ee[tot+tot-2]=(edg){y,z};ee[tot+tot-1]=(edg){x,0};
}
bool bfs(int s,int t)
{
	queue<int> qx;qx.push(s);
	clz(dis);dis[s]=0;
	while(!qx.empty()){
		int x=qx.front();qx.pop();inq[x]=0;
		fe(it,e[x])if(ee[*it].z){
			if(dis[ee[*it].y]>dis[x]+1){
				dis[ee[*it].y]=dis[x]+1;
				if(!inq[ee[*it].y]){
					qx.push(ee[*it].y);
					inq[ee[*it].y]=1;
				}
			}
		}
	}
	return dis[t]<dis[t+1];
}
ll dfs(int x,int tt,ll flw)
{
	if(x==tt||flw==0)return flw;
	ll res=0;
	fe(it,e[x])if(ee[*it].z&&dis[ee[*it].y]==dis[x]+1){
		ll t=dfs(ee[*it].y,tt,min(ee[*it].z,flw));
		res+=t;flw-=t;ee[*it].z-=t;ee[(*it)^1].z+=t;
		if(!flw)break;
	}
	if(flw) dis[x]=-1;
	return res;
}
ll dinic(int s,int t)
{
	ll ans=0;
	while(bfs(s,t)){
		ans+=dfs(s,t,lnf);
	}
	return ans;
}
int main()
{
	read(n);
	rep(i,n){
		int z;read(py[i]);read(px[i]);read(z);
		sum+=z;
		add(i,i+n,z);mp[mk(px[i],py[i])]=i;
	}
	rep(i,n){
		int a=abs(px[i]&1),b=abs(py[i]&1);
		if(a==0){
			if(b==1){
				add(s,i,lnf);
				if(mp.count(mk(px[i],py[i]-1))){
					add(i+n,mp[mk(px[i],py[i]-1)],lnf);
				}
				if(mp.count(mk(px[i],py[i]+1))){
					add(i+n,mp[mk(px[i],py[i]+1)],lnf);
				}
			}
			else{
				if(mp.count(mk(px[i]-1,py[i]))){
					add(i+n,mp[mk(px[i]-1,py[i])],lnf);
				}
				if(mp.count(mk(px[i]+1,py[i]))){
					add(i+n,mp[mk(px[i]+1,py[i])],lnf);
				}
			}
		}
		if(a==1){
			if(b==0){
				if(mp.count(mk(px[i],py[i]-1))){
					add(i+n,mp[mk(px[i],py[i]-1)],lnf);
				}
				if(mp.count(mk(px[i],py[i]+1))){
					add(i+n,mp[mk(px[i],py[i]+1)],lnf);
				}
			}
			else{
				add(i+n,t,lnf);
			}
		}
	}
	cout<<sum-dinic(s,t)<<endl;
	return 0;
}