結果

問題 No.3100 Parallel Translated
コンテスト
ユーザー Astral__
提出日時 2025-04-11 22:14:30
言語 C++23
(gcc 13.3.0 + boost 1.87.0)
結果
AC  
実行時間 4 ms / 2,000 ms
コード長 4,290 bytes
コンパイル時間 6,961 ms
コンパイル使用メモリ 333,976 KB
実行使用メモリ 7,848 KB
最終ジャッジ日時 2025-04-11 22:14:39
合計ジャッジ時間 6,864 ms
ジャッジサーバーID
（参考情報） 		judge2 / judge4
このコードへのチャレンジ
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ファイルパターン 結果
sample AC * 2
other AC * 32
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>
#if __has_include(<atcoder/all>)
#include <atcoder/all>
std::istream &operator>>(std::istream &is, atcoder::modint &v) {
    long long value;
    is >> value;
    v = value;
    return is;
}
std::ostream &operator<<(std::ostream &os, const atcoder::modint &v) {
    os << v.val();
    return os;
}
std::ostream &operator<<(std::ostream &os, const atcoder::modint998244353 &v) {
    os << v.val();
    return os;
}
std::istream &operator>>(std::istream &is, atcoder::modint998244353 &v) {
    long long x;
    is >> x;
    v = x;
    return is;
}
std::ostream &operator<<(std::ostream &os, const atcoder::modint1000000007 &v) {
    os << v.val();
    return os;
}
std::istream &operator>>(std::istream &is, atcoder::modint1000000007 &v) {
    long long x;
    is >> x;
    v = x;
    return is;
}
#endif

using namespace std;
using ll = long long;
using lint = __int128_t;
using pll = pair<ll, ll>;
#define newl '\n';
#define rep(i, s, t) for (ll i = s; i < (ll)(t); i++)
#define rrep(i, s, t) for (ll i = (ll)(t) - 1; i >= (ll)(s); i--)
#define all(x) begin(x), end(x)
#define SZ(x) ll(x.size())
#define eb emplace_back
#define pb push_back
#define TT template <typename T>
TT using vec = vector<T>;
TT using vvec = vec<vec<T>>;
TT using vvvec = vec<vvec<T>>;
TT using minheap = priority_queue<T, vector<T>, greater<T>>;
TT using maxheap = priority_queue<T>;
TT bool chmin(T &x, T y) {
    return x > y ? (x = y, true) : false;
}
TT bool chmax(T &x, T y) {
    return x < y ? (x = y, true) : false;
}
TT T smod(T x, T mod) {
    x %= mod;
    if (x < 0)
        x += mod;
    return x;
}
TT bool rng(T l, T x, T r) {
    return l <= x && x < r;
}
TT T flr(T a, T b) {
    if (b < 0)
        a = -a, b = -b;
    return a >= 0 ? a / b : (a + 1) / b - 1;
}

TT T cil(T a, T b) {
    if (b < 0)
        a = -a, b = -b;
    return a > 0 ? (a - 1) / b + 1 : a / b;
}
TT T sqr(T x) {
    return x * x;
}

//{0, 1, ... } -> {p[0], p[1], ...}
template <typename T, typename S>
void rearrange(vector<T> &A, vector<S> const &p) {
    assert(p.size() == A.size());
    vector<T> a = A;
    for (int i = 0; i < ssize(A); ++i) {
        a[i] = A[p[i]];
    }
    swap(a, A);
}
template <typename T, typename S, typename... Ts>
void rearrange(vector<T> &A, vector<S> p, vector<Ts> &...rest) {
    rearrange(A, p);
    (rearrange(rest, p), ...);
}
template <typename T, typename Compare, typename... Ts>
void rearrange(vector<T> &A, Compare cmp, vector<Ts> &...rest) {
    vector<int> p(ssize(A));
    iota(p.begin(), p.end(), 0);
    sort(p.begin(), p.end(), cmp);
    rearrange(A, p);
    (rearrange(rest, p), ...);
}
struct io_setup {
    io_setup() {
        ios::sync_with_stdio(false);
        std::cin.tie(nullptr);
        cout << fixed << setprecision(15);
    }
} io_setup;

template <class T1, class T2>
ostream &operator<<(ostream &os, const pair<T1, T2> &p) {
    os << p.first << " " << p.second;
    return os;
}

TT ostream &operator<<(ostream &os, const vector<T> &v) {
    for (size_t i = 0; i < v.size(); i++) {
        os << v[i] << (i + 1 != v.size() ? " " : "");
    }
    return os;
}

template <typename T, size_t n>
ostream &operator<<(ostream &os, const array<T, n> &v) {
    for (size_t i = 0; i < n; i++) {
        os << v[i] << (i + 1 != n ? " " : "");
    }
    return os;
}

template <typename T> ostream &operator<<(ostream &os, const vvec<T> &v) {
    for (size_t i = 0; i < v.size(); i++) {
        os << v[i] << (i + 1 != v.size() ? "\n" : "");
    }
    return os;
}

TT istream &operator>>(istream &is, vector<T> &v) {
    for (size_t i = 0; i < v.size(); i++) {
        is >> v[i];
    }
    return is;
}

#if __has_include(<debug/debug.hpp>)
#include <debug/debug.hpp>
#else
#define dbg(...) true
#define DBG(...) true
#define OUT(...) true
#endif
using mint = atcoder::modint998244353;
struct P {
    mint x, y;

    mint cross(P a) {
        return x * a.y - y * a.x;
    }
};
int main() {
    ll n;
    cin >> n;
    vector<P> ps(n);
    rep(i, 0, n) cin >> ps[i].x >> ps[i].y;

    mint ret = 0;
    rep(i, 0, n) {
        ret += ps[i].cross(ps[(i+1)%n]);
    }
    ret /= 2;
    cout << ret << endl;
}

/*
同じ議論を繰り返さない
do smth instead of nothing and stay organized
WRITE STUFF DOWN
DON'T GET STUCK ON ONE APPROACH
*/
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