Submission #858846

#	Time	Username	Problem	Language	Result	Execution time	Memory
858846		LucaIlie	Catfish Farm (IOI22_fish)	C++17	100 / 100	826 ms	279104 KiB

fish

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

using namespace std;

const int MAX_N = 3e5 + 2;
const long long INF = 1e18;
unordered_map<int, long long> costCell[MAX_N], spX[MAX_N];
vector<long long> dp[MAX_N], dpLower[MAX_N], maxPref1[MAX_N], maxSuf2[MAX_N], maxPref3[MAX_N];
vector <int> ys[MAX_N];

long long max_weights( int n, int m, vector <int> X, vector <int> Y, vector <int> W ) {

    for ( int i = 0; i < m; i++ ) {
        X[i]++;
        Y[i]++;
        costCell[X[i]][Y[i]] = W[i];
        ys[X[i] - 1].push_back( Y[i] );
        ys[X[i] + 1].push_back( Y[i] );
    }

    ys[0].clear();
    ys[n + 1].clear();
    for ( int x = 0; x <= n + 1; x++ )
        ys[x].push_back( 0 );
    for ( int x = 0; x <= n + 1; x++ ) {
        sort( ys[x].begin(), ys[x].end() );
        ys[x].resize( unique( ys[x].begin(), ys[x].end() ) - ys[x].begin() );
        dp[x].resize( ys[x].size() );
        dpLower[x].resize( ys[x].size() );
        maxPref1[x].resize( ys[x].size() );
        maxSuf2[x].resize( ys[x].size() );
        maxPref3[x].resize( ys[x].size() );
    }

    for ( int x = 1; x <= n; x++ ) {
        vector<int> yss;
        for ( int i = 0; i < ys[x].size(); i++ )
            yss.push_back( ys[x][i] );
        for ( int i = 0; i < ys[x - 1].size(); i++ )
            yss.push_back( ys[x - 1][i] );
        for ( int i = 0; i < ys[x + 1].size(); i++ )
            yss.push_back( ys[x + 1][i] );
        sort( yss.begin(), yss.end() );
        yss.resize( unique( yss.begin(), yss.end() ) - yss.begin() );
        for ( int i = 1; i < yss.size(); i++ )
            spX[x][yss[i]] = spX[x][yss[i - 1]] + costCell[x][yss[i]];
    }

    dp[0][0] = dpLower[0][0] = 0;
    for ( int x = 1; x <= n + 1; x++ ) {
        int lower1 = 0, upper1 = 0, lower2 = 0, upper2 = 0;
        for ( int i = 0; i < ys[x].size(); i++ ) {
            int crtY = ys[x][i];
            dp[x][i] = dpLower[x][i] = -INF;

            if ( x >= 1 ) {
                while ( lower1 + 1 < ys[x - 1].size() && ys[x - 1][lower1 + 1] <= crtY )
                    lower1++;
                while ( upper1 < ys[x - 1].size() && ys[x - 1][upper1] < crtY )
                    upper1++;

                if ( lower1 >= 0 ) {
                    dpLower[x][i] = max( dpLower[x][i], maxPref1[x - 1][lower1] + spX[x - 1][crtY] );
                    dp[x][i] = max( dp[x][i], maxPref1[x - 1][lower1] + spX[x - 1][crtY] );
                }
                if ( upper1 < ys[x - 1].size() )
                    dp[x][i] = max( dp[x][i], maxSuf2[x - 1][upper1] - spX[x][crtY] );
            }

            if ( x >= 2 ) {
                while ( lower2 + 1 < ys[x - 2].size() && ys[x - 2][lower2 + 1] <= crtY )
                    lower2++;
                while ( upper2 < ys[x - 2].size() && ys[x - 2][upper2] < crtY )
                    upper2++;

                if ( lower2 >= 0 ) {
                    dpLower[x][i] = max( dpLower[x][i], maxPref3[x - 2][lower2] + spX[x - 1][crtY] );
                    dp[x][i] = max( dp[x][i], maxPref3[x - 2][lower2] + spX[x - 1][crtY] );
                }
                if ( upper2 < ys[x - 2].size() ) {
                    dpLower[x][i] = max( dpLower[x][i], maxSuf2[x - 2][upper2] );
                    dp[x][i] = max( dp[x][i], maxSuf2[x - 2][upper2] );
                }
            }

            maxPref1[x][i] = dpLower[x][i] - spX[x][crtY];
            maxSuf2[x][i] = dp[x][i] + spX[x + 1][crtY];
            maxPref3[x][i] = dpLower[x][i];
        }

        for ( int i = 1; i < ys[x].size(); i++ ) {
            maxPref1[x][i] = max( maxPref1[x][i], maxPref1[x][i - 1] );
            maxPref3[x][i] = max( maxPref3[x][i], maxPref3[x][i - 1] );
        }
        for ( int i = ys[x].size() - 2; i >= 0; i-- )
            maxSuf2[x][i] = max( maxSuf2[x][i], maxSuf2[x][i + 1] );
    }

    return dp[n + 1][0];
}

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:38:28: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   38 |         for ( int i = 0; i < ys[x].size(); i++ )
      |                          ~~^~~~~~~~~~~~~~
fish.cpp:40:28: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   40 |         for ( int i = 0; i < ys[x - 1].size(); i++ )
      |                          ~~^~~~~~~~~~~~~~~~~~
fish.cpp:42:28: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   42 |         for ( int i = 0; i < ys[x + 1].size(); i++ )
      |                          ~~^~~~~~~~~~~~~~~~~~
fish.cpp:46:28: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   46 |         for ( int i = 1; i < yss.size(); i++ )
      |                          ~~^~~~~~~~~~~~
fish.cpp:53:28: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   53 |         for ( int i = 0; i < ys[x].size(); i++ ) {
      |                          ~~^~~~~~~~~~~~~~
fish.cpp:58:36: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   58 |                 while ( lower1 + 1 < ys[x - 1].size() && ys[x - 1][lower1 + 1] <= crtY )
      |                         ~~~~~~~~~~~^~~~~~~~~~~~~~~~~~
fish.cpp:60:32: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   60 |                 while ( upper1 < ys[x - 1].size() && ys[x - 1][upper1] < crtY )
      |                         ~~~~~~~^~~~~~~~~~~~~~~~~~
fish.cpp:67:29: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   67 |                 if ( upper1 < ys[x - 1].size() )
      |                      ~~~~~~~^~~~~~~~~~~~~~~~~~
fish.cpp:72:36: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   72 |                 while ( lower2 + 1 < ys[x - 2].size() && ys[x - 2][lower2 + 1] <= crtY )
      |                         ~~~~~~~~~~~^~~~~~~~~~~~~~~~~~
fish.cpp:74:32: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   74 |                 while ( upper2 < ys[x - 2].size() && ys[x - 2][upper2] < crtY )
      |                         ~~~~~~~^~~~~~~~~~~~~~~~~~
fish.cpp:81:29: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   81 |                 if ( upper2 < ys[x - 2].size() ) {
      |                      ~~~~~~~^~~~~~~~~~~~~~~~~~
fish.cpp:92:28: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   92 |         for ( int i = 1; i < ys[x].size(); i++ ) {
      |                          ~~^~~~~~~~~~~~~~

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