#include <bits/stdc++.h>
#include "fish.h"
using namespace std;
using ll = long long;
ll max_weights(
int n, int m, vector<int> x, vector<int> y, vector<int> w) {
vector arr(n+1, vector<pair<int,ll>>());
for (int i = 0; i < m; i++) {
arr[x[i]+1].emplace_back(y[i], w[i]);
}
auto pref = arr;
for (int i = 0; i <= n; i++) {
pref[i] = arr[i];
for (int j = 1; j < pref[i].size(); j++) {
pref[i][j].second += pref[i][j-1].second;
}
}
auto sum = [&](int c, int l, int r) { // [l, r]
auto li = upper_bound(pref[c].begin(), pref[c].end(),
pair{l, 0ll});
auto ri = upper_bound(pref[c].begin(), pref[c].end(),
pair{r, ll(1e18)});
ll ls = li != pref[c].begin() ? (--li)->second : 0;
ll rs = ri != pref[c].begin() ? (--ri)->second : 0;
if (l <= r) return rs - ls;
else return 0ll;
};
vector memo(2, vector(n+1, vector(n+1, -1ll)));
auto dp = [&](auto& dp, bool inc, int c, int h2)->ll{
if (c == n+1) return 0;
ll& res = memo[inc][c][h2];
if (res!=-1) return res;
res = 0;
if (inc) {
for (int h3 = h2; h3 <= n; h3++) {
ll val = sum(c-1, h2, h3-1) + sum(c, h3, h2-1);
res = max(res, val + dp(dp, true, c+1, h3));
res = max(res, val + dp(dp, false, c+1, h3));
}
} else {
for (int h3 = 0; h3 <= h2; h3++) {
ll val = sum(c-1, h2, h3-1) + sum(c, h3, h2-1);
res = max(res, val + dp(dp, false, c+1, h3));
}
}
res = max(res, dp(dp, true, c+1, 0));
return res;
};
ll res = dp(dp, true, 1, 0);
return res;
}
