Submission #1032075

#	Time	Username	Problem	Language	Result	Execution time	Memory
1032075		42kangaroo	Catfish Farm (IOI22_fish)	C++17	9 / 100	92 ms	28752 KiB

fish

#include "fish.h"
#include "bits/stdc++.h"

#include <vector>

struct CaF {
	long long x, w;
};

using ll = long long;

long long max_weights(int N, int M, std::vector<int> X, std::vector<int> Y,
                      std::vector<int> W) {
	using namespace std;
	vector<vector<CaF>> fi(N);
	for (int i = 0; i < N; ++i) {
		fi[i].push_back({-1, 0});
	}
	for (int i = 0; i < M; ++i) {
		fi[X[i]].push_back({Y[i], W[i]});
	}
	for (int i = 0; i < N; ++i) {
		sort(fi[i].begin(), fi[i].end(), [](const CaF &l, const CaF &r) { return l.x < r.x; });
	}
	vector<ll> dpU(fi[0].size()), dpD(fi[0].size());
	for (int i = 1; i < N; ++i) {
		vector<ll> dpNU(fi[i].size()), dpND(fi[i].size());
		int laP = 0;
		ll su = 0;
		ll beSu = 1e9;
		int be = 0;
		for (int j = 0; j < fi[i].size(); ++j) {
			while (laP < fi[i - 1].size() && (j == fi[i].size() - 1 || fi[i - 1][laP].x < fi[i][j + 1].x)) {
				su += fi[i - 1][laP].w;
				if (dpU[laP] - su > dpU[be] - beSu) {
					be = laP;
					beSu = su;
				}
				laP++;
			}
			dpNU[j] = dpU[be] + su - beSu;
		}
		laP = fi[i - 1].size() - 1;
		su = 0;
		beSu = 0;
		be = fi[i - 1].size() - 1;
		for (int j = fi[i].size() - 1; j >= 0; --j) {
			while (laP >= 0 && fi[i - 1][laP].x > fi[i][j].x) {
				laP--;
				if (dpD[laP] - su > dpD[be] - beSu) {
					be = laP;
					beSu = su;
				}
			}
			dpND[j] = max(dpD[be] + su - beSu, dpNU[j]);
			su += fi[i][j].w;
		}
		dpD = dpND;
		dpU = dpNU;
	}
	return max(*max_element(dpU.begin(), dpU.end()), *max_element(dpD.begin(), dpD.end()));
}

Compilation message (stderr)

fish.cpp: In function 'long long int max_weights(int, int, std::vector<int>, std::vector<int>, std::vector<int>)':
fish.cpp:32:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<CaF>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   32 |   for (int j = 0; j < fi[i].size(); ++j) {
      |                   ~~^~~~~~~~~~~~~~
fish.cpp:33:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<CaF>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   33 |    while (laP < fi[i - 1].size() && (j == fi[i].size() - 1 || fi[i - 1][laP].x < fi[i][j + 1].x)) {
      |           ~~~~^~~~~~~~~~~~~~~~~~
fish.cpp:33:40: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<CaF>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   33 |    while (laP < fi[i - 1].size() && (j == fi[i].size() - 1 || fi[i - 1][laP].x < fi[i][j + 1].x)) {
      |                                      ~~^~~~~~~~~~~~~~~~~~~

• Subtask 1: 3 / 3
• Subtask 2: 6 / 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