#include <bits/stdc++.h>
using namespace std;
int N, x[1010], y[1010], c[1010], mem_c, ans = 0;
bool walked[1010] = {0}, plused[1010] = {0};
bool can_walk(int a, int b)
{
    if(walked[b]) return false;
    if(( max(x[a], x[b]) - min(x[a], x[b]) ) + (max(y[a], y[b]) - min(y[a], y[b]) ) == 1) return true;
    else return false;
}
void dfs(int a,int b)
{
    // cout << "Now " << a << " to " << b << endl;
    if(a == N || b == N) return;
    walked[a] = true;
    plused[a] = true;
    mem_c = c[a];
    for(int i = 1; i <= N; ++i)
    {
        if(can_walk(b, i))
        {
            walked[i] = true;
            if(!plused[i])
            {
                mem_c += c[i];
                plused[i] = true;
            }
            ans = max(ans, mem_c);
            dfs(a, i);
        }
    }
    for(int i = b + 1; i <= N; ++i)
    {
        walked[i] = false;
        plused[i] = false;
    }
    dfs(a + 1, a + 1);
    return;
}
int main()
{
    freopen("subset.in", "r", stdin);
    freopen("subset.out", "w", stdout);
    scanf("%d", &N);
    for(int i = 1; i <= N; ++i)
    {
        scanf("%d%d%d", &x[i], &y[i], &c[i]);
    }
    dfs(1, 1);
    printf("%d", ans);
    return 0;
}