Submission #1118143

#	Time	Username	Problem	Language	Result	Execution time	Memory
1118143		Pannda	Bulldozer (JOI17_bulldozer)	C++17	5 / 100	35 ms	604 KiB

bulldozer

#include <bits/stdc++.h>

using namespace std;

#define task "truffle"
#define etr "\n"
#define ll long long
#define ld long double
#define pii pair<int,int>
#define pli pair<long long,int>
#define pll pair<long long, long long>
#define fi first
#define se second
#define bg begin
#define pb push_back
#define pf push_front
#define pob pop_back
#define pof pop_front
#define lwb lower_bound
#define upb upper_bound
#define range(x, l, r) x+l, x+1+r
#define all(x) (x).bg(), (x).end()
#define compact(x) x.resize(unique(all(x)) - (x).bg())
#define sq(x) ((x)*(x))

auto start = chrono::steady_clock::now();

void start_timer()
{
    start = chrono::steady_clock::now();
}

ld elapsed()
{
    auto current = chrono::steady_clock::now();
    ld duration = chrono::duration_cast<chrono::nanoseconds>(current - start).count();
    return duration / 1e9;
}

mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

void freop()
{
    freopen(task".inp", "r", stdin);
    freopen(task".out", "w", stdout);
}

template<class U, class V> istream& operator >> (istream& in, pair<U, V>& p)
{
    in >> p.fi >> p.se;
    return in;
}

template<class U, class V> ostream& operator << (ostream& out, pair<U, V> p)
{
    out << "{" << p.fi << ' ' << p.se << "}";
    return out;
}

template<class T> ostream& operator << (ostream& out, vector<T>& v)
{
    out << "{";
    for (int i=0; i<v.size(); i++)
    {
        out << v[i];
        if (i != v.size() - 1) out << ", ";
    }

    out << "}";
    return out;
}

const int N=2e3, M=1e5, mod=1e9+7;

int n;
array<ll, 3> a[N+5];

namespace Sub1
{
    bool check()
    {
        for (int i=2; i<=n; i++)
        {
            if (a[i][1] != a[i-1][1]) return false;
        }

        return true;
    }

    void solve()
    {
        sort(range(a, 1, n));

        ll Min = 0, val = 0, res = 0;
        for (int i=1; i<=n; i++)
        {
            val += a[i][2];
            if (i == n || a[i][0] != a[i+1][0]) res = max(res, val - Min), Min = min(val, Min);
        }

        cout << res;
    }
}

namespace Sub2
{
    array<ll, 3> b[N+5];

    inline ll f(ll x, ll y, ll u, ll v)
    {
        ll res = 0;
        for (int k=1; k<=n; k++)
        {
            b[k] = a[k];
            b[k][0] = a[k][0] * u + a[k][1] * v;
            b[k][1] = a[k][0] * x + a[k][1] * y;
        }

        sort(range(b, 1, n));

        ll Min = 0, val = 0;
        for (int k=1; k<=n; k++)
        {
            val += b[k][2];
            if (k == n || b[k][0] != b[k+1][0]) res = max(res, val - Min), Min = min(val, Min);
        }

        return res;
    }

    void solve()
    {
        ll res = 0;
        for (int i=1; i<=n; i++)
        {
            for (int j=1; j<i; j++)
            {
                ll x = a[i][0] - a[j][0], y = a[i][1] - a[j][1], u = -y, v = x;
                res = max({res, f(x, y, u, v), f(u, v, x, y)});
            }
        }

        cout << res;
    }
}

namespace Heuristic
{
    array<ll, 3> b[N+5];
    inline ll f(ll x, ll y, ll u, ll v)
    {
        ll res = 0;
        for (int k=1; k<=n; k++)
        {
            b[k] = a[k];
            b[k][0] = a[k][0] * u + a[k][1] * v;
            b[k][1] = a[k][0] * x + a[k][1] * y;
        }

        sort(range(b, 1, n));

        ll Min = 0, val = 0;
        for (int k=1; k<=n; k++)
        {
            val += b[k][2];
            if (k == n || b[k][0] != b[k+1][0]) res = max(res, val - Min), Min = min(val, Min);
        }

        return res;
    }

    void solve()
    {
        shuffle(range(a, 1, n), rng);

        ll res = 0;
        for (int i=1; i<=n; i++)
        {
            for (int j=1; j<=i; j++)
            {
                if (i == j) continue;
                ll x = a[i][0] - a[j][0], y = a[i][1] - a[j][1], u = -y, v = x;
                res = max({res, f(x, y, u, v), f(u, v, x, y)});
            }

            if (elapsed() > 0.85) break;
        }

        cout << res;
    }
}

void process()
{
    cin >> n;
    for (int i=1; i<=n; i++) cin >> a[i][0] >> a[i][1] >> a[i][2];


    if (Sub1::check()) Sub1::solve();
    else if (n <= 100) Sub2::solve();
    else Heuristic::solve();
}

int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(0);

    int t=1; //cin >> t;
    while (t--) process();

    return 0;
}

Compilation message (stderr)

bulldozer.cpp: In function 'void freop()':
bulldozer.cpp:44:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   44 |     freopen(task".inp", "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
bulldozer.cpp:45:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   45 |     freopen(task".out", "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 5 / 5
• Subtask 2: 0 / 20
• Subtask 3: 0 / 35
• Subtask 4: 0 / 20
• Subtask 5: 0 / 20