Submission #464871

#	Time	Username	Problem	Language	Result	Execution time	Memory
464871		ewirlan	Rack (eJOI19_rack)	C++17	40 / 100	140 ms	102404 KiB

rack

//RACK

#define _CTR_SECURE_NO_WARNINGS
#include <iostream>
#include <vector>
typedef long long int ll;
template <typename T> T in()
{
    T x;
    std::cin >> x;
    return x;
}
constexpr int maxn = 1e6 + 3;
constexpr int mod = 1e9 + 7;
ll pow2[maxn]{ 1 };
std::vector <ll> wek{ 1 };
std::vector <ll> wek2;
int main()
{
    std::cin.tie(nullptr); std::cout.tie(nullptr); std::ios_base::sync_with_stdio(0);
    int n(in<int>());
    std::size_t k(in<std::size_t>());
    for (int i(1); i < n; ++i)pow2[i] = (pow2[i - 1] * 2) % mod;
    int j(n);
    while (wek.size() < k)
    {
        --j;
        for (auto i : wek)wek2.push_back((i + pow2[j]) % mod);
        for (auto i : wek2)wek.push_back(i);
        wek2.clear();
    }
    std::cout << wek[k - 1] << '\n';
    return 0;
}

• Subtask 1: 20 / 20
• Subtask 2: 20 / 20
• Subtask 3: 0 / 60