結果

問題 No.2511 Mountain Sequence
ユーザー fastmathfastmath
提出日時 2023-10-20 21:47:28
言語 C++17
(gcc 12.3.0 + boost 1.83.0)
結果
AC  
実行時間 28 ms / 2,000 ms
コード長 6,514 bytes
コンパイル時間 1,664 ms
コンパイル使用メモリ 146,040 KB
実行使用メモリ 12,660 KB
最終ジャッジ日時 2024-09-20 18:08:15
合計ジャッジ時間 2,953 ms
ジャッジサーバーID
（参考情報） 		judge5 / judge4
このコードへのチャレンジ
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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 2 ms
5,248 KB
testcase_01 AC 1 ms
5,376 KB
testcase_02 AC 8 ms
6,400 KB
testcase_03 AC 19 ms
8,960 KB
testcase_04 AC 7 ms
5,888 KB
testcase_05 AC 14 ms
7,936 KB
testcase_06 AC 7 ms
6,400 KB
testcase_07 AC 22 ms
10,624 KB
testcase_08 AC 8 ms
5,760 KB
testcase_09 AC 10 ms
6,272 KB
testcase_10 AC 23 ms
11,232 KB
testcase_11 AC 16 ms
9,472 KB
testcase_12 AC 10 ms
5,888 KB
testcase_13 AC 22 ms
11,512 KB
testcase_14 AC 17 ms
9,984 KB
testcase_15 AC 14 ms
9,552 KB
testcase_16 AC 12 ms
8,576 KB
testcase_17 AC 20 ms
11,008 KB
testcase_18 AC 22 ms
11,452 KB
testcase_19 AC 24 ms
11,904 KB
testcase_20 AC 26 ms
12,520 KB
testcase_21 AC 19 ms
10,752 KB
testcase_22 AC 24 ms
11,404 KB
testcase_23 AC 5 ms
5,376 KB
testcase_24 AC 5 ms
5,376 KB
testcase_25 AC 9 ms
7,680 KB
testcase_26 AC 3 ms
5,376 KB
testcase_27 AC 6 ms
6,144 KB
testcase_28 AC 2 ms
5,376 KB
testcase_29 AC 28 ms
12,660 KB
testcase_30 AC 26 ms
12,348 KB
testcase_31 AC 25 ms
12,448 KB
testcase_32 AC 24 ms
11,516 KB
testcase_33 AC 20 ms
10,496 KB
testcase_34 AC 26 ms
12,140 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 <iostream>
#include <cstdio>
#include <cstdlib>
#include <algorithm>
#include <cmath>
#include <vector>
#include <set>
#include <map>
#include <unordered_set>
#include <unordered_map>
#include <queue>
#include <ctime>
#include <cassert>
#include <complex>
#include <string>
#include <cstring>
#include <chrono>
#include <random>
#include <bitset>
#include <fstream>
#include <array>
#include <functional>
#include <stack>
#include <memory>
using namespace std;
#define int long long
#define ii pair <int, int>
#define app push_back
#define all(a) a.begin(), a.end()
#define bp __builtin_popcountll
#define ll long long
#define mp make_pair
#define x first
#define y second
#define Time (double)clock()/CLOCKS_PER_SEC
#define munq(a) sort(all(a)); a.resize(unique(all(a))-a.begin())
#define sz(a) ((int)a.size())

#ifdef LOCAL
#define debug(x) do { cout << #x << ": " << x << endl; } while(0)
#define debug2(x, y) do { std::cerr << #x << ", " << #y << ": " << x << ", " << y << endl; } while (0)
#define debug3(x, y, z) do {std::cerr << #x << ", " << #y << ", " << #z << ": " << x << ", " << y << ", " << z << endl; } while(0)
#else
#define debug(x)
#define debug2(x, y) 
#define debug3(x, y, z) 
#endif

#define FORI(i,a,b) for (int i = (a); i < (b); ++i)
#define FOR(i,a) FORI(i,0,a)
#define ROFI(i,a,b) for (int i = (b)-1; i >= (a); --i)
#define ROF(i,a) ROFI(i,0,a)
#define rep(a) FOR(_,a)
#define each(a,x) for (auto& a: x)
#define FORN(i, n) FORI(i, 1, n + 1)

using vi = vector<int>;
template <typename T>
std::istream& operator >>(std::istream& input, std::pair <T, T> & data)
{
    input >> data.x >> data.y;
    return input;
}
template <typename T>
std::istream& operator >>(std::istream& input, std::vector<T>& data)
{
    for (T& x : data)
        input >> x;
    return input;
}
template <typename T>
std::ostream& operator <<(std::ostream& output, const pair <T, T> & data)
{
    output << "(" << data.x << "," << data.y << ")";
    return output;
}
template <typename T>
std::ostream& operator <<(std::ostream& output, const std::vector<T>& data)
{
    for (const T& x : data)
        output << x << " ";
    return output;
}
ll div_up(ll a, ll b) { return a/b+((a^b)>0&&a%b); } // divide a by b rounded up
ll div_down(ll a, ll b) { return a/b-((a^b)<0&&a%b); } // divide a by b rounded down 
ll math_mod(ll a, ll b) { return a - b * div_down(a, b); }
#define tcT template<class T
#define tcTU tcT, class U
tcT> using V = vector<T>; 
tcT> bool ckmin(T& a, const T& b) {
    return b < a ? a = b, 1 : 0; 
} // set a = min(a,b)
tcT> bool ckmax(T& a, const T& b) {
    return a < b ? a = b, 1 : 0; 
}
tcT> vector <T> presum(vector <T> &a) {
    vector <T> p(a.size() + 1);
    FOR (i, a.size()) {
        p[i + 1] = p[i] + a[i];
    }   
    return p;
}
tcT> vector <T> sufsum(vector <T> &a) {
    vector <T> p(a.size() + 1);
    for (int i = (int)a.size() - 1; i >= 0; --i) {
        p[i] = p[i + 1] + a[i];
    }
    return p;
}
ll gcd(ll a, ll b) {
    while (b) {
        tie(a, b) = mp(b, a % b);
    }
    return a;
}
int Bit(int mask, int bit) { return (mask >> bit) & 1; }
template<int MOD, int RT> struct mint {
    static const int mod = MOD;
    static constexpr mint rt() { return RT; } // primitive root for FFT
    int v; explicit operator int() const { return v; } // explicit -> don't silently convert to int
    mint() { v = 0; }
    mint(ll _v) { v = (int)((-MOD < _v && _v < MOD) ? _v : _v % MOD);
        if (v < 0) v += MOD; }
    friend bool operator==(const mint& a, const mint& b) { 
        return a.v == b.v; }
    friend bool operator!=(const mint& a, const mint& b) { 
        return !(a == b); }
    friend bool operator<(const mint& a, const mint& b) { 
        return a.v < b.v; }
    friend string ts(mint a) { return to_string(a.v); }

    mint& operator+=(const mint& m) { 
        if ((v += m.v) >= MOD) v -= MOD; 
        return *this; }
    mint& operator-=(const mint& m) { 
        if ((v -= m.v) < 0) v += MOD; 
        return *this; }
    mint& operator*=(const mint& m) { 
        v = (int)((ll)v*m.v%MOD); return *this; }
    mint& operator/=(const mint& m) { return (*this) *= inv(m); }
    friend mint pow(mint a, ll p) {
        mint ans = 1; assert(p >= 0);
        for (; p; p /= 2, a *= a) if (p&1) ans *= a;
        return ans; }
    mint & operator ^=(const int &p) { return (*this) = pow(this, p); }

    friend mint inv(const mint& a) { assert(a.v != 0); 
        return pow(a,MOD-2); }
        
    mint operator-() const { return mint(-v); }
    mint& operator++() { return *this += 1; }
    mint& operator--() { return *this -= 1; }
    friend mint operator+(mint a, const mint& b) { return a += b; }
    friend mint operator-(mint a, const mint& b) { return a -= b; }
    friend mint operator*(mint a, const mint& b) { return a *= b; }
    friend mint operator/(mint a, const mint& b) { return a /= b; }
    friend mint operator^(mint a, const int p) { return pow(a, p); }
};

const int MOD = 998244353;

typedef mint<MOD,5> mi; // 5 is primitive root for both common mods
typedef vector<mi> vmi;

std::ostream& operator << (std::ostream& o, const mi& a)
{
    cout << a.v;
    return o;
}

vector<vmi> scmb; // small combinations
void genComb(int SZ) {
    scmb.assign(SZ,vmi(SZ)); scmb[0][0] = 1;
    FORI(i,1,SZ) FOR(j,i+1) 
        scmb[i][j] = scmb[i-1][j]+(j?scmb[i-1][j-1]:0);
}
 
vmi invs, fac, ifac; // make sure to convert to LL before doing any multiplications ...
void genFac(int SZ) {
    invs.resize(SZ), fac.resize(SZ), ifac.resize(SZ); 
    invs[1] = fac[0] = ifac[0] = 1; 
    FORI(i,2,SZ) invs[i] = mi(-(ll)MOD/i*(int)invs[MOD%i]);
    FORI(i,1,SZ) {
        fac[i] = fac[i-1]*i;
        ifac[i] = ifac[i-1]*invs[i];
    }
}
mi comb(int a, int b) {
    if (a < b || b < 0) return 0;
    assert(a < fac.size());
    return fac[a]*ifac[b]*ifac[a-b];
}
mi partNonNegative(int a, int b) {
    assert(a >= 0);
    if (a == 0 && b == 0) {
        return 1;
    }
    else {
        return comb(a + b - 1, b - 1);
    }
}
mi partPositive(int a, int b) {
    assert(a >= 0);
    if (a == 0 && b == 0) {
        return 1;
    }
    else {
        return comb(a - 1, b - 1);
    }
}
signed main() {
    #ifdef LOCAL
    #else
    #define endl '\n'
    ios_base::sync_with_stdio(0); cin.tie(0);
    #endif
    int n, M;
    cin >> n >> M;
    genFac(n+M);
    mi ans = 0;
    for (int k = 0; 2 * k < n; ++k) {
        int l = n - 1 - 2 * k;
        ans += comb(M, k + l + 1)*comb(k + l, l)*(mi(2)^l);
    }
    cout<<ans<<endl;
}
0