#pragma GCC optimize ("Ofast")
//#pragma GCC target ("avx2")
#include "fish.h"
#include <bits/stdc++.h>
using namespace std;
//#define int long long
#define ll long long
#define vi vector<int>
#define ii pair<int, int>
#define vii vector<ii>
#define tuple3 tuple<int, int, int>
const int N = 1e5+5, inf = INT_MAX;
int n, m;
map<int, int> w[N];
vi c[N];
map<tuple<int, int, int>, ll> dp; // dp[i][j][k] = maximos peces que puedo conseguir
// con las k primeras columnas donde
// en la columna k+1 he subido i-1
// en la columna k+2 he subido j-1
ll mx(int curr, int h1, int h2) {
if (curr == -1) return 0;
tuple3 t = make_tuple(curr, h1, h2);
auto it = dp.find(t);
if (it != dp.end()) return it->second;
dp[t] = mx(curr-1, 0, h1);
it = dp.find(t);
if (curr+1 < n) {
for (int h : c[curr+1]) {
h++;
ll cnt = 0;
// ver si pillo los de la derecha
if (curr+1 < n) {
for (int i = 0; i < h; i++) {
auto it2 = w[curr+1].find(i);
if (it2 != w[curr+1].end() && h2-1 < i && h1-1 < i) cnt += it2->second;
}
}
// ver si pillo los de la izquierda
if (curr-1 >= 0) {
for (int i = 0; i < h; i++) {
auto it2 = w[curr-1].find(i);
if (it2 != w[curr-1].end()) cnt += it2->second;
}
}
// ver si he eliminado alguno de los que he pillado
for (int i = 0; i < min(h, h1); i++) {
auto it2 = w[curr].find(i);
if (it2 != w[curr].end()) cnt -= it2->second;
}
it->second = max(it->second, cnt + mx(curr-1, h, h1));
}
}
if (curr-1 >= 0) {
for (int h : c[curr-1]) {
h++;
ll cnt = 0;
// ver si pillo los de la derecha
if (curr+1 < n) {
for (int i = 0; i < h; i++) {
auto it2 = w[curr+1].find(i);
if (it2 != w[curr+1].end() && h2-1 < i && h1-1 < i) cnt += it2->second;
}
}
// ver si pillo los de la izquierda
if (curr-1 >= 0) {
for (int i = 0; i < h; i++) {
auto it2 = w[curr-1].find(i);
if (it2 != w[curr-1].end()) cnt += it2->second;
}
}
// ver si he eliminado alguno de los que he pillado
for (int i = 0; i < min(h, h1); i++) {
auto it2 = w[curr].find(i);
if (it2 != w[curr].end()) cnt -= it2->second;
}
it->second = max(it->second, cnt + mx(curr-1, h, h1));
}
}
return it->second;
}
long long max_weights(int N, int M, std::vector<int> X, std::vector<int> Y,
std::vector<int> W) {
n = N;
m = M;
for (int i = 0; i < m; i++) {
w[X[i]][Y[i]] = W[i];
c[X[i]].push_back(Y[i]);
}
return mx(n-1, 0, 0);
}
