結果

問題 No.1311 Reverse Permutation Index
ユーザー Haar
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
このコードへのチャレンジ
(要ログイン)
ファイルパターン 結果
sample AC * 2
other AC * 6
権限があれば一括ダウンロードができます

ソースコード

diff #
プレゼンテーションモードにする

#include <bits/stdc++.h>
#ifdef DEBUG
#include <Mylib/Debug/debug.cpp>
#else
#define dump(...) ((void)0)
#endif
template <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;
}
הההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההה
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
0