Submission #841567

#	Time	Username	Problem	Language	Result	Execution time	Memory
841567		LucaIlie	Minerals (JOI19_minerals)	C++17	90 / 100	52 ms	3576 KiB

minerals

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

using namespace std;

const int MAX_N = 43000;
int pairr[2 * MAX_N + 1], perm[2 * MAX_N + 1];
bool inSet[2 * MAX_N + 1];
vector<int> firstt, secondd;
int ans = 0;

void solve( vector <int> &f, vector<int> &s ) {
    if ( f.size() == 1 && s.size() == 1 ) {
        pairr[s[0]] = f[0];
        return;
    }

    vector<int> fl, fr, sl, sr;

    int lis, ris;
    for ( int i = 0; i < f.size() / 2; i++ )
        lis += inSet[i];
    for ( int i = f.size() / 2; i < f.size(); i++ )
        ris += inSet[i];
    if ( lis < ris ) {
        for ( int i = 0; i < f.size() / 2; i++ )
            swap( f[i], f[i + f.size() / 2] );
    }

    int leftt = 0, rightt = 0;
    for ( int i = 0; i < f.size() / 2; i++ ) {
        if ( !inSet[f[i]] ) {
            ans = Query( f[i] );
            inSet[f[i]] = true;
        }
        fl.push_back( f[i] );
        leftt++;
    }
    for ( int i = f.size() / 2; i < f.size(); i++ ) {
        if ( inSet[f[i]] ) {
            ans = Query( f[i] );
            inSet[f[i]] = false;
        }
        fr.push_back( f[i] );
        rightt++;
    }

    random_shuffle( s.begin(), s.end() );
    for ( int i = 0; i < s.size(); i++ ) {
        if ( rightt == 0 ) {
            sl.push_back( s[i] );
            leftt--;
            continue;
        }
        if ( leftt == 0 ) {
            sr.push_back( s[i] );
            rightt--;
            continue;
        }

        int prevAns = ans;
        ans = Query( s[i] );
        inSet[s[i]] ^= 1;

        if ( ans == prevAns ) {
            sl.push_back( s[i] );
            leftt--;
        } else {
            sr.push_back( s[i] );
            rightt--;
        }
    }
    solve( fl, sl );
    solve( fr, sr );
}

void Solve( int n ) {
    for ( int i = 1; i <= 2 * n; i++ )
        perm[i] = i;
    random_shuffle( perm + 1, perm + 1 + 2 * n );

    int prevAns = 0;
    for ( int i = 1; i <= 2 * n; i++ ) {
        if ( firstt.size() == n ) {
            secondd.push_back( perm[i] );
            continue;
        }

        ans = Query( perm[i] );
        inSet[perm[i]] = true;
        if ( ans > prevAns )
            firstt.push_back( perm[i] );
        else
            secondd.push_back( perm[i] );
        prevAns = ans;
    }

    random_shuffle( firstt.begin(), firstt.end() );
    random_shuffle( secondd.begin(), secondd.end() );
    solve( firstt, secondd );

    for ( int i = 0; i < n; i++ )
        Answer( secondd[i], pairr[secondd[i]] );
}

Compilation message (stderr)

minerals.cpp: In function 'void solve(std::vector<int>&, std::vector<int>&)':
minerals.cpp:21:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   21 |     for ( int i = 0; i < f.size() / 2; i++ )
      |                      ~~^~~~~~~~~~~~~~
minerals.cpp:23:35: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   23 |     for ( int i = f.size() / 2; i < f.size(); i++ )
      |                                 ~~^~~~~~~~~~
minerals.cpp:26:28: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   26 |         for ( int i = 0; i < f.size() / 2; i++ )
      |                          ~~^~~~~~~~~~~~~~
minerals.cpp:31:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   31 |     for ( int i = 0; i < f.size() / 2; i++ ) {
      |                      ~~^~~~~~~~~~~~~~
minerals.cpp:39:35: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   39 |     for ( int i = f.size() / 2; i < f.size(); i++ ) {
      |                                 ~~^~~~~~~~~~
minerals.cpp:49:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   49 |     for ( int i = 0; i < s.size(); i++ ) {
      |                      ~~^~~~~~~~~~
minerals.cpp: In function 'void Solve(int)':
minerals.cpp:84:28: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   84 |         if ( firstt.size() == n ) {
      |              ~~~~~~~~~~~~~~^~~~
minerals.cpp: In function 'void solve(std::vector<int>&, std::vector<int>&)':
minerals.cpp:25:5: warning: 'ris' may be used uninitialized in this function [-Wmaybe-uninitialized]
   25 |     if ( lis < ris ) {
      |     ^~
minerals.cpp:25:5: warning: 'lis' may be used uninitialized in this function [-Wmaybe-uninitialized]

• Subtask 1: 6 / 6
• Subtask 2: 25 / 25
• Subtask 3: 9 / 9
• Subtask 4: 30 / 30
• Subtask 5: 5 / 5
• Subtask 6: 5 / 5
• Subtask 7: 5 / 5
• Subtask 8: 5 / 5
• Subtask 9: 0 / 10