結果
問題 | No.1311 Reverse Permutation Index |
ユーザー |
|
提出日時 | 2020-12-08 10:15:27 |
言語 | C++17 (gcc 13.3.0 + boost 1.87.0) |
結果 |
AC
|
実行時間 | 2 ms / 1,500 ms |
コード長 | 3,652 bytes |
コンパイル時間 | 2,731 ms |
コンパイル使用メモリ | 199,240 KB |
最終ジャッジ日時 | 2025-01-16 19:32:36 |
ジャッジサーバーID (参考情報) |
judge3 / judge4 |
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ファイルパターン | 結果 |
---|---|
sample | AC * 2 |
other | AC * 6 |
ソースコード
#include <bits/stdc++.h>#ifdef DEBUG#include <Mylib/Debug/debug.cpp>#else#define dump(...) ((void)0)#endiftemplate <typename T, typename U>bool chmin(T &a, const U &b){return (a > b ? a = b, true : false);}template <typename T, typename U>bool chmax(T &a, const U &b){return (a < b ? a = b, true : false);}template <typename T, size_t N, typename U>void fill_array(T (&a)[N], const U &v){std::fill((U*)a, (U*)(a + N), v);}template <typename T, size_t N, size_t I = N>auto make_vector(const std::array<int, N> &a, T value = T()){static_assert(I >= 1);static_assert(N >= 1);if constexpr (I == 1){return std::vector<T>(a[N - I], value);}else{return std::vector(a[N - I], make_vector<T, N, I - 1>(a, value));}}template <typename T>std::ostream& operator<<(std::ostream &s, const std::vector<T> &a){for(auto it = a.begin(); it != a.end(); ++it){if(it != a.begin()) s << " ";s << *it;}return s;}template <typename T>std::istream& operator>>(std::istream &s, std::vector<T> &a){for(auto &x : a) s >> x;return s;}std::string YesNo(bool value){return value ? "Yes" : "No";}std::string YESNO(bool value){return value ? "YES" : "NO";}std::string yesno(bool value){return value ? "yes" : "no";}template <typename T>void putl(const T &value){std::cout << value << "\n";}template <typename Head, typename ... Tail>void putl(const Head head, const Tail &... tail){std::cout << head << " ";putl(tail ...);}namespace haar_lib {std::vector<int> index_to_permutation(int64_t N, int S){std::vector<int> ret;std::vector<int> nums(S);std::iota(nums.begin(), nums.end(), 0);int64_t p = 1;for(int i = 1; i <= S; ++i) p *= i;for(int i = 0; i < S; ++i){p /= S - i;int64_t index = N / p;for(int j = 0, k = -1; j < S; ++j){if(nums[j] >= 0){++k;if(k == index){ret.push_back(j);nums[j] = -1;break;}}}N %= p;}return ret;}int64_t permutation_to_index(const std::vector<int> &a){const int N = a.size();int64_t ret = 0;std::vector<int> nums(N);std::iota(nums.begin(), nums.end(), 0);int64_t p = 1;for(int i = 1; i <= N; ++i) p *= i;for(int i = 0; i < N; ++i){p /= N - i;for(int j = 0, k = -1; j < N; ++j){if(nums[j] >= 0){++k;if(nums[j] == a[i]){ret += p * k;nums[j] = -1;break;}}}}return ret;}std::vector<int> inverse_permutation(const std::vector<int> &a){const int N = a.size();std::vector<int> ret(N);for(int i = 0; i < N; ++i){ret[a[i]] = i;}return ret;}}namespace solver {using namespace haar_lib;constexpr int m1000000007 = 1000000007;constexpr int m998244353 = 998244353;void init(){std::cin.tie(0);std::ios::sync_with_stdio(false);std::cout << std::fixed << std::setprecision(12);std::cerr << std::fixed << std::setprecision(12);std::cin.exceptions(std::ios_base::failbit);}void solve(){int64_t N, S; std::cin >> N >> S;auto p = index_to_permutation(N, S);p = inverse_permutation(p);int64_t ans = permutation_to_index(p);std::cout << ans << "\n";}}int main(){solver::init();while(true){try{solver::solve();std::cout << std::flush;std::cerr << std::flush;}catch(const std::istream::failure &e){break;}catch(...){break;}}return 0;}