Submission #841588

#	Time	Username	Problem	Language	Result	Execution time	Memory
841588		LucaIlie	Minerals (JOI19_minerals)	C++17	100 / 100	45 ms	3812 KiB

minerals

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

using namespace std;

const int MAX_N = 43000;
int perm[2 * MAX_N + 1];
bool inSet[2 * MAX_N + 1];
vector<int> firstt, secondd;
int ans = 0;
auto seed = default_random_engine( 69696 );

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

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

    bool status = inSet[f[0]] ^ 1;

    int mid = (f.size() < 10 ? f.size() / 2 : min( (int)f.size() - 1, ((int)(f.size() * 0.369))) );

    int leftt = 0, rightt = 0;
    for ( int i = 0; i < mid; i++ ) {
        if ( inSet[f[i]] != status ) {
            ans = Query( f[i] );
            inSet[f[i]] = status;
        }
        fl.push_back( f[i] );
        leftt++;
    }
    for ( int i = mid; i < f.size(); i++ ) {
        if ( inSet[f[i]] == status ) {
            ans = Query( f[i] );
            inSet[f[i]] = status ^ 1;
        }
        fr.push_back( f[i] );
        rightt++;
    }

    shuffle( s.begin(), s.end(), seed );
    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 ( (status == true && ans == prevAns) || (status == false && 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;
    shuffle( perm + 1, perm + 1 + 2 * n, seed );

    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;
    }

    shuffle( firstt.begin(), firstt.end(), seed );
    shuffle( secondd.begin(), secondd.end(), seed );
    solve( firstt, secondd );
}

Compilation message (stderr)

minerals.cpp: In function 'void solve(std::vector<int>&, std::vector<int>&)':
minerals.cpp:34:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   34 |     for ( int i = mid; i < f.size(); i++ ) {
      |                        ~~^~~~~~~~~~
minerals.cpp:44:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   44 |     for ( int i = 0; i < s.size(); i++ ) {
      |                      ~~^~~~~~~~~~
minerals.cpp: In function 'void Solve(int)':
minerals.cpp:79:28: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   79 |         if ( firstt.size() == n ) {
      |              ~~~~~~~~~~~~~~^~~~

• 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: 10 / 10