結果
| 問題 |
No.2406 Difference of Coordinate Squared
|
| コンテスト | |
| ユーザー |
 cn_449
|
| 提出日時 | 2023-08-04 21:56:14 |
| 言語 | C++17 (gcc 13.3.0 + boost 1.87.0) |
| 結果 |
WA
(最新)
AC
(最初)
|
| 実行時間 | - |
| コード長 | 5,828 bytes |
| コンパイル時間 | 1,516 ms |
| コンパイル使用メモリ | 132,444 KB |
| 最終ジャッジ日時 | 2025-02-15 22:40:40 |
|
ジャッジサーバーID （参考情報） |
judge2 / judge2 |
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| ファイルパターン | 結果 |
|---|---|
| sample | AC * 2 |
| other | AC * 54 WA * 1 |
ソースコード
#include <iostream>
#include <vector>
#include <algorithm>
#include <cmath>
#include <string>
#include <queue>
#include <stack>
#include <set>
#include <map>
#include <iomanip>
#include <utility>
#include <tuple>
#include <functional>
#include <bitset>
#include <cassert>
#include <complex>
#include <stdio.h>
#include <time.h>
#include <numeric>
#include <random>
#include <unordered_set>
#include <unordered_map>
#define all(a) (a).begin(), (a).end()
#define rep(i, n) for (ll i = 0; i < (n); i++)
#define req(i, a, b) for (ll i = (a); i < (b); i++)
#define pb push_back
#define debug(x) cerr << __LINE__ << ' ' << #x << ':' << (x) << '\n'
#define debug2(x, y) cerr << __LINE__ << ' ' << #x << ':' << (x) << ',' << #y << ':' << (y) << '\n'
#define debug3(x, y, z) cerr << __LINE__ << ' ' << #x << ':' << (x) << ',' << #y << ':' << (y) << ',' << #z << ':' << (z) << '\n'
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
using namespace std;
typedef long long ll;
typedef unsigned int uint;
typedef unsigned long long ull;
typedef long double ld;
template<class T> using P = pair<T, T>;
template<class T> using pri_s = priority_queue<T, vector<T>, greater<T>>;
template<class T> using pri_b = priority_queue<T>;
constexpr int inf = 1000000010;
constexpr int inf2 = 2000000010;
constexpr ll INF = 1000000000000000010;
constexpr ll INF4 = 4000000000000000010;
constexpr int mod1e9 = 1000000007;
constexpr int mod998 = 998244353;
constexpr ld eps = 1e-12;
constexpr ld pi = 3.141592653589793238;
constexpr ll ten(int n) { return n ? 10 * ten(n - 1) : 1; };
int dx[] = { 1,0,-1,0,1,1,-1,-1,0 }; int dy[] = { 0,1,0,-1,1,-1,1,-1,0 };
ll mul(ll a, ll b) { return (b != 0 && a > INF / b ? INF : a * b); }
void fail() { cout << "-1\n"; exit(0); } void no() { cout << "No\n"; exit(0); }
template<class T> void er(T a) { cout << a << '\n'; exit(0); }
template<class T, class U> inline bool chmax(T& a, const U& b) { if (a < b) { a = b; return true; } return false; }
template<class T, class U> inline bool chmin(T& a, const U& b) { if (a > b) { a = b; return true; } return false; }
template<class T> istream& operator >>(istream& s, vector<T>& v) { for (auto& e : v) s >> e; return s; }
template<class T> ostream& operator <<(ostream& s, const vector<T>& v) { for (auto& e : v) s << e << ' '; return s; }
template<class T> ostream& operator <<(ostream& s, const set<T>& v) { for (auto& e : v) s << e << ' '; return s; }
template<class T> ostream& operator <<(ostream& s, const multiset<T>& v) { for (auto& e : v) s << e << ' '; return s; }
template<class T, class U> ostream& operator << (ostream& s, const pair<T, U>& p) { s << p.first << ' ' << p.second; return s; }
struct fastio {
fastio() {
cin.tie(0); cout.tie(0);
ios::sync_with_stdio(false);
cout << fixed << setprecision(20);
cerr << fixed << setprecision(20);
}
}fastio_;
constexpr ll mod = mod998;
template <int mod> class modint {
public:
int n;
modint() : n(0) {};
modint(ll n_) {
n = n_ % mod;
if (n < 0) n += mod;
}
modint operator -() const { return n > 0 ? mod - n : -n; }
bool operator == (const modint& m) const { return n == m.n; }
bool operator != (const modint& m) const { return n != m.n; }
modint& operator += (const modint& m) { n += m.n; if (n >= mod) n -= mod; return *this; }
modint& operator -= (const modint& m) { n -= m.n; if (n < 0) n += mod; return *this; }
modint& operator *= (const modint& m) { n = ll(n) * m.n % mod; return *this; }
modint& operator /= (const modint& m) { n = ll(n) * modinv(m).n % mod; return *this; }
modint operator +(modint m) const { return modint(*this) += m; }
modint operator -(modint m) const { return modint(*this) -= m; }
modint operator *(modint m) const { return modint(*this) *= m; }
modint operator /(modint m) const { return modint(*this) /= m; }
modint& operator ++ () { *this += 1; return *this; }
modint operator ++ (int) { *this += 1; return *this - 1; }
modint& operator -- () { *this -= 1; return *this; }
modint operator -- (int) { *this -= 1; return *this + 1; }
modint pow(ll b) const {
modint res = 1, a = modint(*this);
while (b) {
if (b & 1) res *= a;
a *= a;
b >>= 1;
}
return res;
}
friend istream& operator >> (istream& s, modint<mod>& a) { s >> a.n; return s; }
friend ostream& operator << (ostream& s, modint<mod>& a) { s << a.n; return s; }
};
using mint = modint<mod>;
vector<mint> fac, inv, facinv;
mint modinv(mint x) {
ll a = x.n;
if (a == 0) abort();
if (a < (ll)inv.size()) return inv[a];
ll b = mod, u = 1, v = 0;
while (b) {
ll t = a / b;
a -= t * b; swap(a, b);
u -= t * v; swap(u, v);
}
mint res = u;
return res;
}
void modcalc(int n) {
fac.resize(n); inv.resize(n); facinv.resize(n);
fac[0] = 1; fac[1] = 1; inv[1] = 1;
facinv[0] = 1; facinv[1] = 1;
for (ll i = 2; i < n; i++) {
fac[i] = fac[i - 1] * i;
inv[i] = -inv[mod % i] * (mod / i);
facinv[i] = facinv[i - 1] * inv[i];
}
}
mint comb(ll n, ll k) {
if (n < 0 || k < 0 || n < k) return 0;
return fac[n] * facinv[k] * facinv[n - k];
}
mint perm(ll n, ll k) {
if (n < 0 || k < 0 || n < k) return 0;
return fac[n] * facinv[n - k];
}
mint hom(ll n, ll k) {
if (n < 0 || k < 0 || n == 0 && k > 0) return 0;
if (n == 0 && k == 0) return 1;
return fac[n + k - 1] * facinv[k] * facinv[n - 1];
}
mint f(ll n, ll x, ll y) {
if (abs(x) + abs(y) > n) return 0;
ll a = (x + y + n) / 2;
ll b = (x - y + n) / 2;
return comb(n, a) * comb(n, b);
}
bool is_square(ll n) {
if (n < 0) return false;
ll r = sqrtl(n);
return r * r == n;
}
int main() {
modcalc(2 * ten(6) + 10);
ll n, m;
cin >> n >> m;
mint ans = 0;
for (ll y = -ten(6); y <= ten(6); y++) {
ll xx = y * y + m;
if (is_square(xx)) {
ll x = sqrtl(xx);
ans += f(n, x, y);
if (x != 0) ans += f(n, -x, y);
}
}
ans /= mint(4).pow(n);
cout << ans << '\n';
}