結果

問題 No.2089 置換の符号
ユーザー r1933r1933
提出日時 2022-09-30 21:51:07
言語 C++17
(gcc 13.2.0 + boost 1.83.0)
結果
AC  
実行時間 3 ms / 2,000 ms
コード長 5,243 bytes
コンパイル時間 1,964 ms
コンパイル使用メモリ 203,188 KB
実行使用メモリ 4,380 KB
最終ジャッジ日時 2023-08-24 15:19:55
合計ジャッジ時間 3,418 ms
ジャッジサーバーID
（参考情報） 		judge11 / judge15
このコードへのチャレンジ（β）

テストケース

テストケース表示
入力 結果 実行時間
実行使用メモリ
testcase_00 AC 1 ms
4,376 KB
testcase_01 AC 1 ms
4,376 KB
testcase_02 AC 1 ms
4,376 KB
testcase_03 AC 2 ms
4,376 KB
testcase_04 AC 2 ms
4,376 KB
testcase_05 AC 2 ms
4,376 KB
testcase_06 AC 1 ms
4,380 KB
testcase_07 AC 1 ms
4,380 KB
testcase_08 AC 2 ms
4,376 KB
testcase_09 AC 1 ms
4,380 KB
testcase_10 AC 2 ms
4,376 KB
testcase_11 AC 2 ms
4,376 KB
testcase_12 AC 1 ms
4,380 KB
testcase_13 AC 1 ms
4,376 KB
testcase_14 AC 2 ms
4,376 KB
testcase_15 AC 2 ms
4,380 KB
testcase_16 AC 1 ms
4,376 KB
testcase_17 AC 2 ms
4,376 KB
testcase_18 AC 2 ms
4,376 KB
testcase_19 AC 1 ms
4,380 KB
testcase_20 AC 1 ms
4,380 KB
testcase_21 AC 1 ms
4,376 KB
testcase_22 AC 1 ms
4,380 KB
testcase_23 AC 2 ms
4,380 KB
testcase_24 AC 1 ms
4,376 KB
testcase_25 AC 1 ms
4,380 KB
testcase_26 AC 1 ms
4,380 KB
testcase_27 AC 1 ms
4,380 KB
testcase_28 AC 2 ms
4,380 KB
testcase_29 AC 3 ms
4,380 KB
testcase_30 AC 2 ms
4,376 KB
testcase_31 AC 2 ms
4,376 KB
testcase_32 AC 2 ms
4,380 KB
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 # 

#include "bits/stdc++.h"
#pragma GCC optimize("Ofast")

// Begin Header {{{
#pragma region
using namespace std;

#ifndef DEBUG
#define dump(...)
#endif

#define all(x) begin(x), end(x)
#define rall(x) rbegin(x), rend(x)
#define rep(i, b, e) for (intmax_t i = (b), i##_limit = (e); i < i##_limit; ++i)
#define repc(i, b, e) for (intmax_t i = (b), i##_limit = (e); i <= i##_limit; ++i)
#define repr(i, b, e) for (intmax_t i = (b), i##_limit = (e); i >= i##_limit; --i)
#define var(Type, ...) \
    Type __VA_ARGS__;  \
    input(__VA_ARGS__)
#define let const auto

constexpr size_t operator""_zu(unsigned long long value) {
    return value;
};
constexpr intmax_t operator""_jd(unsigned long long value) {
    return value;
};
constexpr uintmax_t operator""_ju(unsigned long long value) {
    return value;
};

constexpr int INF = 0x3f3f3f3f;
constexpr intmax_t LINF = 0x3f3f3f3f3f3f3f3f_jd;

using usize = size_t;
using imax = intmax_t;
using uimax = uintmax_t;
using ld = long double;

template <class T, class Compare = less<>>
using MaxHeap = priority_queue<T, vector<T>, Compare>;
template <class T, class Compare = greater<>>
using MinHeap = priority_queue<T, vector<T>, Compare>;

inline void input() {}
template <class Head, class... Tail>
inline void input(Head&& head, Tail&&... tail) {
    cin >> head;
    input(forward<Tail>(tail)...);
}

template <class Container, class Value = typename Container::value_type,
          enable_if_t<!is_same<Container, string>::value, nullptr_t> = nullptr>
inline istream& operator>>(istream& is, Container& vs) {
    for (auto& v: vs) is >> v;
    return is;
}

template <class T, class U>
inline istream& operator>>(istream& is, pair<T, U>& p) {
    is >> p.first >> p.second;
    return is;
}

inline void output() {
    cout << "\n";
}
template <class Head, class... Tail>
inline void output(Head&& head, Tail&&... tail) {
    cout << head;
    if (sizeof...(tail)) cout << " ";
    output(forward<Tail>(tail)...);
}

template <class Container, class Value = typename Container::value_type,
          enable_if_t<!is_same<Container, string>::value, nullptr_t> = nullptr>
inline ostream& operator<<(ostream& os, const Container& vs) {
    static constexpr const char* delim[] = {" ", ""};
    for (auto it = begin(vs); it != end(vs); ++it) {
        os << delim[it == begin(vs)] << *it;
    }
    return os;
}

template <class Iterator>
inline void join(const Iterator& Begin, const Iterator& End, const string& delim = "\n",
                 const string& last = "\n") {
    for (auto it = Begin; it != End; ++it) {
        cout << ((it == Begin) ? "" : delim) << *it;
    }
    cout << last;
}

template <class T>
inline vector<T> makeVector(const T& init_value, size_t sz) {
    return vector<T>(sz, init_value);
}

template <class T, class... Args>
inline auto makeVector(const T& init_value, size_t sz, Args... args) {
    return vector<decltype(makeVector<T>(init_value, args...))>(
        sz, makeVector<T>(init_value, args...));
}

template <class Func>
class FixPoint : Func {
public:
    explicit constexpr FixPoint(Func&& f) noexcept : Func(forward<Func>(f)) {}

    template <class... Args>
    constexpr decltype(auto) operator()(Args&&... args) const {
        return Func::operator()(*this, std::forward<Args>(args)...);
    }
};

template <class Func>
static inline constexpr decltype(auto) makeFixPoint(Func&& f) noexcept {
    return FixPoint<Func> {forward<Func>(f)};
}

template <class Container>
struct reverse_t {
    Container& c;
    reverse_t(Container& c) : c(c) {}
    auto begin() {
        return c.rbegin();
    }
    auto end() {
        return c.rend();
    }
};

template <class Container>
auto reversed(Container& c) {
    return reverse_t<Container>(c);
}

template <class T>
inline bool chmax(T& a, const T& b) noexcept {
    return b > a && (a = b, true);
}

template <class T>
inline bool chmin(T& a, const T& b) noexcept {
    return b < a && (a = b, true);
}

template <class T>
inline T diff(const T& a, const T& b) noexcept {
    return a < b ? b - a : a - b;
}

template <class T>
inline T sigma(const T& l, const T& r) noexcept {
    return (l + r) * (r - l + 1) / 2;
}

template <class T>
inline T ceildiv(const T& n, const T& d) noexcept {
    return (n + d - 1) / d;
}

void operator|=(vector<bool>::reference lhs, const bool rhs) {
    lhs = lhs | rhs;
}

void operator&=(vector<bool>::reference lhs, const bool rhs) {
    lhs = lhs & rhs;
}

void operator^=(vector<bool>::reference lhs, const bool rhs) {
    lhs = lhs ^ rhs;
}

void ioinit() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    cout << fixed << setprecision(10);
    cerr << fixed << setprecision(10);
    clog << fixed << setprecision(10);
}
#pragma endregion
// }}} End Header

int main() {
    ioinit();

    var(size_t, N);

    vector<int> as(N);
    for (auto&& a: as) input(a), a--;

    vector<bool> seen(N, false);
    int sum = 0;
    rep(i, 0, N) {
        if (seen[i]) continue;
        int cur = i, cnt = 0;
        do {
            seen[cur] = true;
            cur = as[cur];
            cnt++;
        } while (cur != i);
        sum += cnt - 1;
    }

    if (sum & 1) {
        output(-1);
    } else {
        output(1);
    }
    return 0;
}
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