This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include <bits/stdc++.h>
// #include "prison.h"
// #pragma GCC optimize("Ofast")
// #pragma GCC target("avx2")
// #pragma GCC target("popcnt")
using namespace std;
 
using ll = long long;
using ull = unsigned long long;
using lld = long double;
using vi = vector<int>;
using vll = vector<ll>;
using ii = pair<int,int>;
using pll = pair<ll, ll>;
using vii = vector<ii>;
using vpll = vector<pll>;
 
#define endl '\n'
#define all(x) x.begin(),x.end()
#define lsb(x) x&(-x)
#define gcd(a,b) __gcd(a,b)
#define sz(x) (int)x.size()
#define mp make_pair
#define pb push_back
#define fi first
#define se second
#define fls cout.flush()
 
#define fore(i,l,r) for(auto i=l;i<r;i++)
#define fo(i,n) fore(i,0,n)
#define forex(i,r,l) for(auto i=r; i>=l;i--)
#define ffo(i,n) forex(i,n-1,0)
bool cmin(int &a, int b){if(b<a){a=b;return 1;}return 0;}
bool cmax(int &a, int b){if(b>a){a=b;return 1;}return 0;}
void valid(ll in){cout<<((in)?"YES\n":"NO\n");}
ll lcm(ll a, ll b){return (a/gcd(a,b))*b;}
ll gauss(ll n){return (n*(n+1))/2;}
const int N = 3000;
ll dp[N][N][3];
ll max_weights(int n,int m,vi x,vi y,vi w) {
    vector<vll> arr(n+4, vll(n+4, 0)), pf(n+4, vll(n+4, 0));
    fo(i, m) x[i]++, y[i]++;
    fo(i, m) arr[x[i]][y[i]] = w[i];
    fore(i, 1, n+1) {
        fore(j, 1, n+1) {
            pf[i][j] = (i ? pf[i][j-1] : 0) + arr[i][j];
        }
    }
    auto gets = [&](int i,int l,int r) {
        if(l > r) return 0ll;
        assert(l >= 1);
        return pf[i][r] - pf[i][l-1];
    };
    ll ans = 0;
    fore(i, 2, n+1) {
        fo(c, n+1) {
            fo(d, n+1) {
                dp[i][c][0] = max({dp[i][c][0], dp[i-1][d][0], dp[i-1][d][1] + gets(i-1, 1, c) - gets(i-1, 1, d), dp[i-1][d][2]});
                dp[i][c][1] = max({dp[i][c][1], dp[i-1][d][0], dp[i-1][d][1] + gets(i-1, 1, c) - gets(i-1, 1, d), dp[i-1][d][2]});
                ll s = gets(i, 1, d) - gets(i, 1, c);
                dp[i][c][2] = max({dp[i][c][2] - s, dp[i-1][d][0], dp[i-1][d][1] + gets(i-1, 1, c) - gets(i-1, 1, d), dp[i-1][d][2]}) + s;
            }
            assert(dp[i][c][0] == dp[i][c][1]);
            ans = max(ans, max(dp[i][c][2], dp[i][c][0]));
        }
    }
    return ans;
}
// void test_case() {
//     int n, m;
//     cin >> n >> m;
//     vi x(m), y(m), w(m);
//     fo(i, m) cin >> x[i] >> y[i] >> w[i];
//     cout << max_weights(n, m, x, y, w) << '\n';   
// }
// int main(){cin.tie(0)->sync_with_stdio(0);
//     int t=1;
//     // cin >> t;
//     while(t--)test_case();
// }
| # | Verdict  | Execution time | Memory | Grader output | 
|---|
| Fetching results... | 
| # | Verdict  | Execution time | Memory | Grader output | 
|---|
| Fetching results... | 
| # | Verdict  | Execution time | Memory | Grader output | 
|---|
| Fetching results... | 
| # | Verdict  | Execution time | Memory | Grader output | 
|---|
| Fetching results... | 
| # | Verdict  | Execution time | Memory | Grader output | 
|---|
| Fetching results... | 
| # | Verdict  | Execution time | Memory | Grader output | 
|---|
| Fetching results... | 
| # | Verdict  | Execution time | Memory | Grader output | 
|---|
| Fetching results... | 
| # | Verdict  | Execution time | Memory | Grader output | 
|---|
| Fetching results... |