結果
問題 | No.2511 Mountain Sequence |
ユーザー |
👑 ![]() |
提出日時 | 2023-10-20 23:08:27 |
言語 | C++17(gcc12) (gcc 12.3.0 + boost 1.87.0) |
結果 |
WA
|
実行時間 | - |
コード長 | 3,343 bytes |
コンパイル時間 | 22,748 ms |
コンパイル使用メモリ | 353,332 KB |
最終ジャッジ日時 | 2025-02-17 10:50:57 |
ジャッジサーバーID (参考情報) |
judge3 / judge4 |
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ファイルパターン | 結果 |
---|---|
sample | AC * 2 WA * 1 |
other | AC * 4 WA * 28 |
ソースコード
#pragma GCC target("avx2") #pragma GCC optimize("O3") #pragma GCC optimize("unroll-loops") #include <bits/stdc++.h> #include <atcoder/all> using namespace std; using namespace atcoder; typedef long long ll; #define rep(i, n) for (int i = 0; i < (int)(n); i++) #define repr(i, n) for (int i = (int)(n)-1; i >= 0; i--) #define repk(i, k, n) for (int i = k; i < (int)(n); i++) #define all(v) v.begin(), v.end() #define mod1 1000000007 #define mod2 998244353 #define mod3 100000007 #define vi vector<int> #define vs vector<string> #define vc vector<char> #define vl vector<ll> #define vb vector<bool> #define vvi vector<vector<int>> #define vvc vector<vector<char>> #define vvl vector<vector<ll>> #define vvb vector<vector<bool>> #define vvvi vector<vector<vector<int>>> #define vvvl vector<vector<vector<ll>>> #define pii pair<int, int> #define pil pair<int, ll> #define pli pair<ll, int> #define pll pair<ll, ll> #define vpii vector<pair<int, int>> #define vpll vector<pair<ll, ll>> #define vvpii vector<vector<pair<int, int>>> #define vvpll vector<vector<pair<ll, ll>>> template <typename T> void debug(T e) { cerr << e << endl; } template <typename T> void debug(vector<T> &v) { rep(i, v.size()) { cerr << v[i] << " "; } cerr << endl; } template <typename T> void debug(vector<vector<T>> &v) { rep(i, v.size()) { rep(j, v[i].size()) { cerr << v[i][j] << " "; } cerr << endl; } } template <typename T> void debug(vector<pair<T, T>> &v) { rep(i, v.size()) { cerr << v[i].first << " " << v[i].second << endl; } } template <typename T> void debug(set<T> &st) { for (auto itr = st.begin(); itr != st.end(); itr++) { cerr << *itr << " "; } cerr << endl; } template <typename T> void debug(multiset<T> &ms) { for (auto itr = ms.begin(); itr != ms.end(); itr++) { cerr << *itr << " "; } cerr << endl; } template <typename T> void debug(map<T, T> &mp) { for (auto itr = mp.begin(); itr != mp.end(); itr++) { cerr << itr->first << " " << itr->second << endl; } } void debug_out() { cerr << endl; } template <typename Head, typename... Tail> void debug_out(Head H, Tail... T) { cerr << H << " "; debug_out(T...); } ll my_pow(ll x, ll n, ll mod) { // 繰り返し二乗法.x^nをmodで割った余り. ll ret; if (n == 0) { ret = 1; } else if (n % 2 == 1) { ret = (x * my_pow((x * x) % mod, n / 2, mod)) % mod; } else { ret = my_pow((x * x) % mod, n / 2, mod); } return ret; } ll inv(ll x, ll mod) { return my_pow(x, mod - 2, mod); } int main() { ll N, M; cin >> N >> M; if (N == 1) { cout << M << endl; return 0; } ll ans = 0; for (ll i = 1; i <= N; i++) { ll form = i; ll latt = N + 1 - i; if (max(form, latt) > M) { continue; } ll min_val = min(form, latt); ll max_val = max(form, latt); ll anssub = my_pow(min_val, max_val - min_val, mod2); ll hi = (min_val * max_val) % mod2; ll prod = my_pow(hi, M - max_val + 1, mod2); prod = (prod + mod2 - 1) % mod2; prod = (prod * inv((hi + mod2 - 1) % mod2, mod2)) % mod2; ans = (ans + anssub * prod) % mod2; // debug_out(i, max_val, hi, prod); } cout << ans << endl; }