Submission #969065

#	Time	Username	Problem	Language	Result	Execution time	Memory
969065		CyberCow	A Difficult(y) Choice (BOI21_books)	C++17	20 / 100	158 ms	3612 KiB

books

#include "books.h"
#include <vector>
#include <algorithm>
#include <cmath>
#include <map>
#include <set>

using namespace std;
using ll = long long;
const int N = 100010;
long long v[N];

void solve(int n, int k, long long a, int s) {

    if (n == s)
    {
        set<pair<long long, int>> se;
        for (int i = 1; i <= n; i++)
        {
            v[i] = skim(i);
            se.insert({ v[i], i });
        }
        int st = 0;
        ll sum = 0;
        for (int i = 1; i <= k; i++)
        {
            sum += v[i];
        }
        for (int i = k; i <= n; i++)
        {
            if (sum >= a && sum <= 2 * a)
            {
                vector<int> ans;
                for (int j = i - k + 1; j <= i; j++)
                {
                    ans.push_back(j);
                }
                answer(ans);
                return;
            }
            sum += v[i + 1] - v[i - k + 1];
        }
        sum = 0;
        for (int i = 1; i <= k - 1; i++)
        {
            sum += v[i];
        }
        for (int i = k; i <= n; i++)
        {
            if (sum + v[i] >= a && sum + v[i] <= 2 * a)
            {
                vector<int> ans;
                for (int j = 1; j < k; j++)
                {
                    ans.push_back(j);
                }
                ans.push_back(i);
                answer(ans);
                return;
            }
        }
        impossible();
    }
    set<pair<long long, int>> se;
    for (int i = 1; i <= n; i++)
    {
        v[i] = skim(i);
        se.insert({ v[i], i });
    }
    int st = 0;
    ll sum = 0;
    for (int i = 1; i <= k - 1; i++)
    {
        sum += v[i];
    }
    int l = k, r = n, m = 0, ans;
    while (l <= r)
    {
        m = (l + r) / 2;
        int x = skim(m);
        if (sum + x <= 2 * a && sum + x >= a)
        {
            vector<int> ans;
            for (int j = 1; j < k; j++)
            {
                ans.push_back(j);
            }
            ans.push_back(m);
            answer(ans);
            return;
        }
        else if(sum + x > 2 * a)
        {
            r = m - 1;
        }
        else
        {
            l = m + 1;
        }
    }
    l = 1, r = n - k + 1, m = 0, ans;
    while (l <= r)
    {
        m = (l + r) / 2;
        sum = 0;
        for (int i = m; i < m + k; i++)
        {
            sum += skim(i);
        }
        if (sum > 2 * a)
        {
            r = m - 1;
        }
        else if (sum < a)
        {
            l = m + 1;
        }
        else
        {
            vector<int> ans;
            for (int j = m; j < m + k; j++)
            {
                ans.push_back(j);
            }
            answer(ans);
            return;
        }
    }
    impossible();
}

Compilation message (stderr)

books.cpp: In function 'void solve(int, int, long long int, int)':
books.cpp:23:13: warning: unused variable 'st' [-Wunused-variable]
   23 |         int st = 0;
      |             ^~
books.cpp:101:37: warning: right operand of comma operator has no effect [-Wunused-value]
  101 |     l = 1, r = n - k + 1, m = 0, ans;
      |                                     ^
books.cpp:70:9: warning: unused variable 'st' [-Wunused-variable]
   70 |     int st = 0;
      |         ^~

• Subtask 1: 5 / 5
• Subtask 2: 15 / 15
• Subtask 3: 0 / 10
• Subtask 4: 0 / 15
• Subtask 5: 0 / 15
• Subtask 6: 0 / 20
• Subtask 7: 0 / 20