結果
| 問題 | No.1740 Alone 'a' |
| ユーザー |
 rniya
|
| 提出日時 | 2021-11-12 21:48:29 |
| 言語 | C++17 (gcc 13.3.0 + boost 1.87.0) |
| 結果 |
AC
|
| 実行時間 | 27 ms / 2,000 ms |
| コード長 | 9,112 bytes |
| コンパイル時間 | 1,859 ms |
| コンパイル使用メモリ | 200,196 KB |
| 最終ジャッジ日時 | 2025-01-25 16:23:44 |
|
ジャッジサーバーID （参考情報） |
judge5 / judge3 |
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| ファイルパターン | 結果 |
|---|---|
| sample | AC * 3 |
| other | AC * 38 |
ソースコード
#define LOCAL#include <bits/stdc++.h>using namespace std;#pragma region Macrostypedef long long ll;typedef __int128_t i128;typedef unsigned int uint;typedef unsigned long long ull;#define ALL(x) (x).begin(), (x).end()template <typename T> istream& operator>>(istream& is, vector<T>& v) {for (T& x : v) is >> x;return is;}template <typename T> 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, typename U> ostream& operator<<(ostream& os, const pair<T, U>& p) {os << '(' << p.first << ',' << p.second << ')';return os;}template <typename T, typename U> ostream& operator<<(ostream& os, const map<T, U>& m) {os << '{';for (auto itr = m.begin(); itr != m.end();) {os << '(' << itr->first << ',' << itr->second << ')';if (++itr != m.end()) os << ',';}os << '}';return os;}template <typename T, typename U> ostream& operator<<(ostream& os, const unordered_map<T, U>& m) {os << '{';for (auto itr = m.begin(); itr != m.end();) {os << '(' << itr->first << ',' << itr->second << ')';if (++itr != m.end()) os << ',';}os << '}';return os;}template <typename T> ostream& operator<<(ostream& os, const set<T>& s) {os << '{';for (auto itr = s.begin(); itr != s.end();) {os << *itr;if (++itr != s.end()) os << ',';}os << '}';return os;}template <typename T> ostream& operator<<(ostream& os, const multiset<T>& s) {os << '{';for (auto itr = s.begin(); itr != s.end();) {os << *itr;if (++itr != s.end()) os << ',';}os << '}';return os;}template <typename T> ostream& operator<<(ostream& os, const unordered_set<T>& s) {os << '{';for (auto itr = s.begin(); itr != s.end();) {os << *itr;if (++itr != s.end()) os << ',';}os << '}';return os;}template <typename T> ostream& operator<<(ostream& os, const deque<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 <int i, typename T> void print_tuple(ostream&, const T&) {}template <int i, typename T, typename H, class... Args> void print_tuple(ostream& os, const T& t) {if (i) os << ',';os << get<i>(t);print_tuple<i + 1, T, Args...>(os, t);}template <typename... Args> ostream& operator<<(ostream& os, const tuple<Args...>& t) {os << '{';print_tuple<0, tuple<Args...>, Args...>(os, t);return os << '}';}void debug_out() { cerr << '\n'; }template <class Head, class... Tail> void debug_out(Head&& head, Tail&&... tail) {cerr << head;if (sizeof...(Tail) > 0) cerr << ", ";debug_out(move(tail)...);}#ifdef LOCAL#define debug(...) \cerr << " "; \cerr << #__VA_ARGS__ << " :[" << __LINE__ << ":" << __FUNCTION__ << "]" << '\n'; \cerr << " "; \debug_out(__VA_ARGS__)#else#define debug(...) void(0)#endiftemplate <typename T> T gcd(T x, T y) { return y != 0 ? gcd(y, x % y) : x; }template <typename T> T lcm(T x, T y) { return x / gcd(x, y) * y; }int topbit(signed t) { return t == 0 ? -1 : 31 - __builtin_clz(t); }int topbit(long long t) { return t == 0 ? -1 : 63 - __builtin_clzll(t); }int botbit(signed a) { return a == 0 ? 32 : __builtin_ctz(a); }int botbit(long long a) { return a == 0 ? 64 : __builtin_ctzll(a); }int popcount(signed t) { return __builtin_popcount(t); }int popcount(long long t) { return __builtin_popcountll(t); }bool ispow2(int i) { return i && (i & -i) == i; }long long MSK(int n) { return (1LL << n) - 1; }template <class T> T ceil(T x, T y) {assert(y >= 1);return (x > 0 ? (x + y - 1) / y : x / y);}template <class T> T floor(T x, T y) {assert(y >= 1);return (x > 0 ? x / y : (x - y + 1) / y);}template <class T1, class T2> inline bool chmin(T1& a, T2 b) {if (a > b) {a = b;return true;}return false;}template <class T1, class T2> inline bool chmax(T1& a, T2 b) {if (a < b) {a = b;return true;}return false;}template <typename T> void mkuni(vector<T>& v) {sort(v.begin(), v.end());v.erase(unique(v.begin(), v.end()), v.end());}template <typename T> int lwb(const vector<T>& v, const T& x) { return lower_bound(v.begin(), v.end(), x) - v.begin(); }#pragma endregion#include <cassert>#include <cstdint>#include <iostream>template <uint64_t Modulus> class modint {using i64 = int64_t;using u32 = uint32_t;using u64 = uint64_t;static_assert(Modulus < static_cast<uint32_t>(1) << 31, "Modulus must be less than 2**31");static constexpr u32 mod = Modulus;u32 v;public:constexpr modint(const i64 x = 0) noexcept : v(x < 0 ? mod - 1 - (-(x + 1) % mod) : x % mod) {}constexpr u32& val() noexcept { return v; }constexpr const u32& val() const noexcept { return v; }constexpr modint operator+(const modint& rhs) const noexcept { return modint(*this) += rhs; }constexpr modint operator-(const modint& rhs) const noexcept { return modint(*this) -= rhs; }constexpr modint operator*(const modint& rhs) const noexcept { return modint(*this) *= rhs; }constexpr modint operator/(const modint& rhs) const noexcept { return modint(*this) /= rhs; }constexpr modint& operator+=(const modint& rhs) noexcept {v += rhs.v;if (v >= mod) v -= mod;return *this;}constexpr modint& operator-=(const modint& rhs) noexcept {if (v < rhs.v) v += mod;v -= rhs.v;return *this;}constexpr modint& operator*=(const modint& rhs) noexcept {v = (u64)v * rhs.v % mod;return *this;}constexpr modint& operator/=(const modint& rhs) noexcept { return *this *= rhs.inv(); }constexpr modint pow(long long n) const noexcept {assert(0 <= n);modint self(*this), res(1);while (n > 0) {if (n & 1) res *= self;self *= self;n >>= 1;}return res;}constexpr modint inv() const noexcept {assert(*this != 0);return pow(mod - 2);}constexpr modint& operator++() noexcept {if (++v == mod) v = 0;return *this;}constexpr modint& operator--() noexcept {if (v == 0) v = mod;return --v, *this;}constexpr modint operator++(int) noexcept {modint t = *this;return ++*this, t;}constexpr modint operator--(int) noexcept {modint t = *this;return --*this, t;}constexpr modint operator-() const noexcept { return modint(mod - v); }template <class T> friend constexpr modint operator+(T x, modint y) noexcept { return modint(x) + y; }template <class T> friend constexpr modint operator-(T x, modint y) noexcept { return modint(x) - y; }template <class T> friend constexpr modint operator*(T x, modint y) noexcept { return modint(x) * y; }template <class T> friend constexpr modint operator/(T x, modint y) noexcept { return modint(x) / y; }constexpr bool operator==(const modint& rhs) const noexcept { return v == rhs.v; }constexpr bool operator!=(const modint& rhs) const noexcept { return v != rhs.v; }constexpr bool operator!() const noexcept { return !v; }friend std::istream& operator>>(std::istream& s, modint& rhs) noexcept {i64 v;rhs = modint{(s >> v, v)};return s;}friend std::ostream& operator<<(std::ostream& s, const modint& rhs) noexcept { return s << rhs.v; }};/*** @brief modint* @docs docs/modulo/modint.md*/const int INF = 1e9;const long long IINF = 1e18;const int dx[4] = {1, 0, -1, 0}, dy[4] = {0, 1, 0, -1};const char dir[4] = {'D', 'R', 'U', 'L'};// const long long MOD = 1000000007;const long long MOD = 998244353;using mint = modint<MOD>;int main() {cin.tie(0);ios::sync_with_stdio(false);int N;string S;cin >> N >> S;vector<vector<mint>> cnt(N + 1, vector<mint>(2, 0));cnt[0][0] = 1;for (int i = 0; i < N; i++) {cnt[i + 1][0] += cnt[i][0] * 25;cnt[i + 1][1] += cnt[i][0];cnt[i + 1][1] += cnt[i][1] * 25;}mint ans = 0;int a = 0;for (int i = 0; i < N; i++) {int x = S[i] - 'a';for (int j = 0; j < x; j++) {int na = a + (j == 0);if (na > 1) continue;ans += cnt[N - 1 - i][1 - na];}if (x == 0) a++;}cout << ans << '\n';return 0;}