Submission #720201

#	Time	Username	Problem	Language	Result	Execution time	Memory
720201		baojiaopisu	Catfish Farm (IOI22_fish)	C++17	3 / 100	348 ms	86632 KiB

fish

#include<bits/stdc++.h>

using namespace std;

using ll = long long;
using ld = long double;
using ull = unsigned long long;

using pii = pair<int, int>;
using pll = pair<ll, ll>;
using pld = pair<ld, ld>;

#define fi first
#define se second
#define left BAO
#define right ANH
#define pb push_back
#define pf push_front
#define mp make_pair
#define ins insert
#define btpc __builtin_popcount
#define btclz __builtin_clz

#define sz(x) (int)(x.size());
#define all(x) x.begin(), x.end()
#define debug(...) " [" << #__VA_ARGS__ ": " << (__VA_ARGS__) << "] "

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

int d4x[4] = {1, 0, -1, 0}; int d4y[4] = {0, 1, 0, -1};
int d8x[8] = {0, 1, 1, 1, 0, -1, -1, -1};
int d8y[8] = {1, 1, 0, -1, -1, -1, 0, 1};

template<class X, class Y>
    bool minimize(X &x, const Y &y) {
        if (x > y)
        {
            x = y;
            return true;
        }
        return false;
    }
template<class X, class Y>
    bool maximize(X &x, const Y &y) {
        if (x < y)
        {
            x = y;
            return true;
        }
        return false;
    }

const int MOD = 1e9 + 7; //998244353

template<class X, class Y>
	void add(X &x, const Y &y) {
		x = (x + y);
		if(x >= MOD) x -= MOD;
	}

template<class X, class Y> 
	void sub(X &x, const Y &y) {
		x = (x - y);
		if(x < 0) x += MOD;
	}

/* Author : Le Ngoc Bao Anh, 12A5, LQD High School for Gifted Student*/

const ll INF = 1e9;
const int N = 2e5 + 10;

struct Data {
	int t, y, w;
};
vector<Data> fish[N];
vector<ll> dp[N], pref[N], pref2[N], suff[N];
ll f[N];

ll max_weights(int n, int m, vector<int> x, vector<int> y, vector<int> w) {
	for(int i = 0; i < m; i++) {
		if(x[i] > 0) fish[x[i] - 1].pb({1, y[i], w[i]});
		fish[x[i]].pb({0, y[i], w[i]});
		fish[x[i] + 1].pb({-1, y[i], w[i]});
	}

	for(int i = 0; i < n; i++) {
		sort(all(fish[i]), [&](Data x, Data y) {
			if(x.y == y.y) return (x.t == 0);
			return x.y < y.y;
		});
	}

	ll ans = 0;
	for(int i = 0; i < n; i++) {
		ll left = 0;
		ll right = 0;
		ll hide = 0;

		dp[i].resize(fish[i].size() + 2);
		for(int j = 0; j < fish[i].size(); j++) {
			if(fish[i][j].t == -1) left += fish[i][j].w;
			if(fish[i][j].t == 0) hide += fish[i][j].w;
			if(fish[i][j].t == 1) right += fish[i][j].w;
			dp[i][j] = left + right;
			if(i >= 3) maximize(dp[i][j], left + right + f[i - 3]);
			if(i >= 2) {
				int l = 0, r = fish[i - 2].size() - 1, pos = -1;
				while(l <= r) {
					int mid = (l + r) >> 1;
					if(fish[i - 2][mid].y >= fish[i][j].y) {
						pos = mid;
						r = mid - 1;
					} else l = mid + 1;
				}
				if(pos >= 0) maximize(dp[i][j], right + suff[i - 2][pos]);
				if(pos == -1) pos = fish[i - 2].size();
				pos--;
				if(pos >= 0) maximize(dp[i][j], right + left + pref[i - 2][pos]);
			}

			if(i >= 1 && (i % 2 == 0)) {
				int l = 0, r = fish[i - 1].size() - 1, pos = -1;
				while(l <= r) {
					int mid = (l + r) >> 1;
					if(fish[i - 1][mid].y >= fish[i][j].y) {
						pos = mid;
						r = mid - 1;
					} else l = mid + 1;
				}
				if(pos >= 0) maximize(dp[i][j], right - hide + suff[i - 1][pos]);
				if(pos == -1) pos = fish[i - 1].size();
				pos--;
				assert(!left && !right);
				if(pos >= 0) maximize(dp[i][j], right + left + pref2[i - 1][pos]);
			}
		}

		suff[i].resize(fish[i].size() + 2);
		pref[i] = pref2[i] = suff[i];
		for(int j = fish[i].size(); j >= 0; j--) {
			suff[i][j] = max(suff[i][j + 1], dp[i][j]);
		}

		left = right = hide = 0;
		for(int j = 0; j < fish[i].size(); j++) {
			if(fish[i][j].t == -1) left += fish[i][j].w;
			if(fish[i][j].t == 0) hide += fish[i][j].w;
			if(fish[i][j].t == 1) right += fish[i][j].w;
			pref[i][j] = dp[i][j] - right;
			pref2[i][j] = dp[i][j] - right - hide;
			if(j > 0) {
				maximize(pref[i][j], pref[i][j - 1]);
				maximize(pref2[i][j], pref2[i][j - 1]);
			}
		}

		for(int j = 0; j < fish[i].size(); j++) maximize(f[i], dp[i][j]);
		if(i > 0) maximize(f[i], f[i - 1]);
		maximize(ans, f[i]);
	}

	return ans;
}

Compilation message (stderr)

fish.cpp: In function 'll max_weights(int, int, std::vector<int>, std::vector<int>, std::vector<int>)':
fish.cpp:100:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<Data>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  100 |   for(int j = 0; j < fish[i].size(); j++) {
      |                  ~~^~~~~~~~~~~~~~~~
fish.cpp:145:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<Data>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  145 |   for(int j = 0; j < fish[i].size(); j++) {
      |                  ~~^~~~~~~~~~~~~~~~
fish.cpp:157:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<Data>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  157 |   for(int j = 0; j < fish[i].size(); j++) maximize(f[i], dp[i][j]);
      |                  ~~^~~~~~~~~~~~~~~~

• Subtask 1: 3 / 3
• Subtask 2: 0 / 6
• Subtask 3: 0 / 9
• Subtask 4: 0 / 14
• Subtask 5: 0 / 21
• Subtask 6: 0 / 17
• Subtask 7: 0 / 14
• Subtask 8: 0 / 16