結果
問題 | No.1294 マウンテン数列 |
ユーザー | yosupot |
提出日時 | 2020-11-20 21:57:49 |
言語 | C++17 (gcc 12.3.0 + boost 1.83.0) |
結果 |
AC
|
実行時間 | 33 ms / 2,000 ms |
コード長 | 27,866 bytes |
コンパイル時間 | 1,318 ms |
コンパイル使用メモリ | 126,332 KB |
実行使用メモリ | 6,944 KB |
最終ジャッジ日時 | 2024-07-23 12:57:43 |
合計ジャッジ時間 | 2,111 ms |
ジャッジサーバーID (参考情報) |
judge1 / judge5 |
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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
6,812 KB |
testcase_01 | AC | 2 ms
6,944 KB |
testcase_02 | AC | 2 ms
6,944 KB |
testcase_03 | AC | 2 ms
6,940 KB |
testcase_04 | AC | 2 ms
6,940 KB |
testcase_05 | AC | 8 ms
6,940 KB |
testcase_06 | AC | 10 ms
6,940 KB |
testcase_07 | AC | 2 ms
6,940 KB |
testcase_08 | AC | 2 ms
6,944 KB |
testcase_09 | AC | 2 ms
6,944 KB |
testcase_10 | AC | 30 ms
6,944 KB |
testcase_11 | AC | 31 ms
6,944 KB |
testcase_12 | AC | 30 ms
6,940 KB |
testcase_13 | AC | 31 ms
6,940 KB |
testcase_14 | AC | 33 ms
6,940 KB |
testcase_15 | AC | 29 ms
6,940 KB |
testcase_16 | AC | 32 ms
6,940 KB |
ソースコード
//#pragma GCC optimize("Ofast") //#pragma GCC target("avx") //#undef LOCAL #include <cassert> #include <numeric> #include <type_traits> #ifdef _MSC_VER #include <intrin.h> #endif #include <utility> #ifdef _MSC_VER #include <intrin.h> #endif namespace atcoder { namespace internal { constexpr long long safe_mod(long long x, long long m) { x %= m; if (x < 0) x += m; return x; } struct barrett { unsigned int _m; unsigned long long im; barrett(unsigned int m) : _m(m), im((unsigned long long)(-1) / m + 1) {} unsigned int umod() const { return _m; } unsigned int mul(unsigned int a, unsigned int b) const { unsigned long long z = a; z *= b; #ifdef _MSC_VER unsigned long long x; _umul128(z, im, &x); #else unsigned long long x = (unsigned long long)(((unsigned __int128)(z)*im) >> 64); #endif unsigned int v = (unsigned int)(z - x * _m); if (_m <= v) v += _m; return v; } }; constexpr long long pow_mod_constexpr(long long x, long long n, int m) { if (m == 1) return 0; unsigned int _m = (unsigned int)(m); unsigned long long r = 1; unsigned long long y = safe_mod(x, m); while (n) { if (n & 1) r = (r * y) % _m; y = (y * y) % _m; n >>= 1; } return r; } constexpr bool is_prime_constexpr(int n) { if (n <= 1) return false; if (n == 2 || n == 7 || n == 61) return true; if (n % 2 == 0) return false; long long d = n - 1; while (d % 2 == 0) d /= 2; constexpr long long bases[3] = {2, 7, 61}; for (long long a : bases) { long long t = d; long long y = pow_mod_constexpr(a, t, n); while (t != n - 1 && y != 1 && y != n - 1) { y = y * y % n; t <<= 1; } if (y != n - 1 && t % 2 == 0) { return false; } } return true; } template <int n> constexpr bool is_prime = is_prime_constexpr(n); constexpr std::pair<long long, long long> inv_gcd(long long a, long long b) { a = safe_mod(a, b); if (a == 0) return {b, 0}; long long s = b, t = a; long long m0 = 0, m1 = 1; while (t) { long long u = s / t; s -= t * u; m0 -= m1 * u; // |m1 * u| <= |m1| * s <= b auto tmp = s; s = t; t = tmp; tmp = m0; m0 = m1; m1 = tmp; } if (m0 < 0) m0 += b / s; return {s, m0}; } constexpr int primitive_root_constexpr(int m) { if (m == 2) return 1; if (m == 167772161) return 3; if (m == 469762049) return 3; if (m == 754974721) return 11; if (m == 998244353) return 3; int divs[20] = {}; divs[0] = 2; int cnt = 1; int x = (m - 1) / 2; while (x % 2 == 0) x /= 2; for (int i = 3; (long long)(i)*i <= x; i += 2) { if (x % i == 0) { divs[cnt++] = i; while (x % i == 0) { x /= i; } } } if (x > 1) { divs[cnt++] = x; } for (int g = 2;; g++) { bool ok = true; for (int i = 0; i < cnt; i++) { if (pow_mod_constexpr(g, (m - 1) / divs[i], m) == 1) { ok = false; break; } } if (ok) return g; } } template <int m> constexpr int primitive_root = primitive_root_constexpr(m); } // namespace internal } // namespace atcoder #include <cassert> #include <numeric> #include <type_traits> namespace atcoder { namespace internal { #ifndef _MSC_VER template <class T> using is_signed_int128 = typename std::conditional<std::is_same<T, __int128_t>::value || std::is_same<T, __int128>::value, std::true_type, std::false_type>::type; template <class T> using is_unsigned_int128 = typename std::conditional<std::is_same<T, __uint128_t>::value || std::is_same<T, unsigned __int128>::value, std::true_type, std::false_type>::type; template <class T> using make_unsigned_int128 = typename std::conditional<std::is_same<T, __int128_t>::value, __uint128_t, unsigned __int128>; template <class T> using is_integral = typename std::conditional<std::is_integral<T>::value || is_signed_int128<T>::value || is_unsigned_int128<T>::value, std::true_type, std::false_type>::type; template <class T> using is_signed_int = typename std::conditional<(is_integral<T>::value && std::is_signed<T>::value) || is_signed_int128<T>::value, std::true_type, std::false_type>::type; template <class T> using is_unsigned_int = typename std::conditional<(is_integral<T>::value && std::is_unsigned<T>::value) || is_unsigned_int128<T>::value, std::true_type, std::false_type>::type; template <class T> using to_unsigned = typename std::conditional< is_signed_int128<T>::value, make_unsigned_int128<T>, typename std::conditional<std::is_signed<T>::value, std::make_unsigned<T>, std::common_type<T>>::type>::type; #else template <class T> using is_integral = typename std::is_integral<T>; template <class T> using is_signed_int = typename std::conditional<is_integral<T>::value && std::is_signed<T>::value, std::true_type, std::false_type>::type; template <class T> using is_unsigned_int = typename std::conditional<is_integral<T>::value && std::is_unsigned<T>::value, std::true_type, std::false_type>::type; template <class T> using to_unsigned = typename std::conditional<is_signed_int<T>::value, std::make_unsigned<T>, std::common_type<T>>::type; #endif template <class T> using is_signed_int_t = std::enable_if_t<is_signed_int<T>::value>; template <class T> using is_unsigned_int_t = std::enable_if_t<is_unsigned_int<T>::value>; template <class T> using to_unsigned_t = typename to_unsigned<T>::type; } // namespace internal } // namespace atcoder namespace atcoder { namespace internal { struct modint_base {}; struct static_modint_base : modint_base {}; template <class T> using is_modint = std::is_base_of<modint_base, T>; template <class T> using is_modint_t = std::enable_if_t<is_modint<T>::value>; } // namespace internal template <int m, std::enable_if_t<(1 <= m)>* = nullptr> struct static_modint : internal::static_modint_base { using mint = static_modint; public: static constexpr int mod() { return m; } static mint raw(int v) { mint x; x._v = v; return x; } static_modint() : _v(0) {} template <class T, internal::is_signed_int_t<T>* = nullptr> static_modint(T v) { long long x = (long long)(v % (long long)(umod())); if (x < 0) x += umod(); _v = (unsigned int)(x); } template <class T, internal::is_unsigned_int_t<T>* = nullptr> static_modint(T v) { _v = (unsigned int)(v % umod()); } static_modint(bool v) { _v = ((unsigned int)(v) % umod()); } unsigned int val() const { return _v; } mint& operator++() { _v++; if (_v == umod()) _v = 0; return *this; } mint& operator--() { if (_v == 0) _v = umod(); _v--; return *this; } mint operator++(int) { mint result = *this; ++*this; return result; } mint operator--(int) { mint result = *this; --*this; return result; } mint& operator+=(const mint& rhs) { _v += rhs._v; if (_v >= umod()) _v -= umod(); return *this; } mint& operator-=(const mint& rhs) { _v -= rhs._v; if (_v >= umod()) _v += umod(); return *this; } mint& operator*=(const mint& rhs) { unsigned long long z = _v; z *= rhs._v; _v = (unsigned int)(z % umod()); return *this; } mint& operator/=(const mint& rhs) { return *this = *this * rhs.inv(); } mint operator+() const { return *this; } mint operator-() const { return mint() - *this; } mint pow(long long n) const { assert(0 <= n); mint x = *this, r = 1; while (n) { if (n & 1) r *= x; x *= x; n >>= 1; } return r; } mint inv() const { if (prime) { assert(_v); return pow(umod() - 2); } else { auto eg = internal::inv_gcd(_v, m); assert(eg.first == 1); return eg.second; } } friend mint operator+(const mint& lhs, const mint& rhs) { return mint(lhs) += rhs; } friend mint operator-(const mint& lhs, const mint& rhs) { return mint(lhs) -= rhs; } friend mint operator*(const mint& lhs, const mint& rhs) { return mint(lhs) *= rhs; } friend mint operator/(const mint& lhs, const mint& rhs) { return mint(lhs) /= rhs; } friend bool operator==(const mint& lhs, const mint& rhs) { return lhs._v == rhs._v; } friend bool operator!=(const mint& lhs, const mint& rhs) { return lhs._v != rhs._v; } private: unsigned int _v; static constexpr unsigned int umod() { return m; } static constexpr bool prime = internal::is_prime<m>; }; template <int id> struct dynamic_modint : internal::modint_base { using mint = dynamic_modint; public: static int mod() { return (int)(bt.umod()); } static void set_mod(int m) { assert(1 <= m); bt = internal::barrett(m); } static mint raw(int v) { mint x; x._v = v; return x; } dynamic_modint() : _v(0) {} template <class T, internal::is_signed_int_t<T>* = nullptr> dynamic_modint(T v) { long long x = (long long)(v % (long long)(mod())); if (x < 0) x += mod(); _v = (unsigned int)(x); } template <class T, internal::is_unsigned_int_t<T>* = nullptr> dynamic_modint(T v) { _v = (unsigned int)(v % mod()); } dynamic_modint(bool v) { _v = ((unsigned int)(v) % mod()); } unsigned int val() const { return _v; } mint& operator++() { _v++; if (_v == umod()) _v = 0; return *this; } mint& operator--() { if (_v == 0) _v = umod(); _v--; return *this; } mint operator++(int) { mint result = *this; ++*this; return result; } mint operator--(int) { mint result = *this; --*this; return result; } mint& operator+=(const mint& rhs) { _v += rhs._v; if (_v >= umod()) _v -= umod(); return *this; } mint& operator-=(const mint& rhs) { _v += mod() - rhs._v; if (_v >= umod()) _v -= umod(); return *this; } mint& operator*=(const mint& rhs) { _v = bt.mul(_v, rhs._v); return *this; } mint& operator/=(const mint& rhs) { return *this = *this * rhs.inv(); } mint operator+() const { return *this; } mint operator-() const { return mint() - *this; } mint pow(long long n) const { assert(0 <= n); mint x = *this, r = 1; while (n) { if (n & 1) r *= x; x *= x; n >>= 1; } return r; } mint inv() const { auto eg = internal::inv_gcd(_v, mod()); assert(eg.first == 1); return eg.second; } friend mint operator+(const mint& lhs, const mint& rhs) { return mint(lhs) += rhs; } friend mint operator-(const mint& lhs, const mint& rhs) { return mint(lhs) -= rhs; } friend mint operator*(const mint& lhs, const mint& rhs) { return mint(lhs) *= rhs; } friend mint operator/(const mint& lhs, const mint& rhs) { return mint(lhs) /= rhs; } friend bool operator==(const mint& lhs, const mint& rhs) { return lhs._v == rhs._v; } friend bool operator!=(const mint& lhs, const mint& rhs) { return lhs._v != rhs._v; } private: unsigned int _v; static internal::barrett bt; static unsigned int umod() { return bt.umod(); } }; template <int id> internal::barrett dynamic_modint<id>::bt = 998244353; using modint998244353 = static_modint<998244353>; using modint1000000007 = static_modint<1000000007>; using modint = dynamic_modint<-1>; namespace internal { template <class T> using is_static_modint = std::is_base_of<internal::static_modint_base, T>; template <class T> using is_static_modint_t = std::enable_if_t<is_static_modint<T>::value>; template <class> struct is_dynamic_modint : public std::false_type {}; template <int id> struct is_dynamic_modint<dynamic_modint<id>> : public std::true_type {}; template <class T> using is_dynamic_modint_t = std::enable_if_t<is_dynamic_modint<T>::value>; } // namespace internal } // namespace atcoder #include <unistd.h> #include <algorithm> #include <array> #include <cctype> #include <cstring> #include <string> #include <type_traits> #include <vector> namespace yosupo { namespace internal { int ceil_pow2(int n) { int x = 0; while ((1U << x) < (unsigned int)(n)) x++; return x; } } // namespace internal int bsf(unsigned int n) { return __builtin_ctz(n); } int bsf(unsigned long n) { return __builtin_ctzl(n); } int bsf(unsigned long long n) { return __builtin_ctzll(n); } int bsr(unsigned int n) { return 8 * (int)sizeof(unsigned int) - 1 - __builtin_clz(n); } int bsr(unsigned long n) { return 8 * (int)sizeof(unsigned long) - 1 - __builtin_clzl(n); } int bsr(unsigned long long n) { return 8 * (int)sizeof(unsigned long long) - 1 - __builtin_clzll(n); } } // namespace yosupo #include <cassert> #include <numeric> #include <type_traits> namespace yosupo { namespace internal { template <class T> using is_signed_int128 = typename std::conditional<std::is_same<T, __int128_t>::value || std::is_same<T, __int128>::value, std::true_type, std::false_type>::type; template <class T> using is_unsigned_int128 = typename std::conditional<std::is_same<T, __uint128_t>::value || std::is_same<T, unsigned __int128>::value, std::true_type, std::false_type>::type; template <class T> using make_unsigned_int128 = typename std::conditional<std::is_same<T, __int128_t>::value, __uint128_t, unsigned __int128>; template <class T> using is_integral = typename std::conditional<std::is_integral<T>::value || internal::is_signed_int128<T>::value || internal::is_unsigned_int128<T>::value, std::true_type, std::false_type>::type; template <class T> using is_signed_int = typename std::conditional<(is_integral<T>::value && std::is_signed<T>::value) || is_signed_int128<T>::value, std::true_type, std::false_type>::type; template <class T> using is_unsigned_int = typename std::conditional<(is_integral<T>::value && std::is_unsigned<T>::value) || is_unsigned_int128<T>::value, std::true_type, std::false_type>::type; template <class T> using to_unsigned = typename std::conditional< is_signed_int128<T>::value, make_unsigned_int128<T>, typename std::conditional<std::is_signed<T>::value, std::make_unsigned<T>, std::common_type<T>>::type>::type; template <class T> using is_integral_t = std::enable_if_t<is_integral<T>::value>; template <class T> using is_signed_int_t = std::enable_if_t<is_signed_int<T>::value>; template <class T> using is_unsigned_int_t = std::enable_if_t<is_unsigned_int<T>::value>; template <class T> using to_unsigned_t = typename to_unsigned<T>::type; } // namespace internal } // namespace yosupo namespace yosupo { struct Scanner { public: Scanner(FILE* fp) : fd(fileno(fp)) {} void read() {} template <class H, class... T> void read(H& h, T&... t) { bool f = read_single(h); assert(f); read(t...); } int read_unsafe() { return 0; } template <class H, class... T> int read_unsafe(H& h, T&... t) { bool f = read_single(h); if (!f) return 0; return 1 + read_unsafe(t...); } private: static constexpr size_t SIZE = 1 << 15; bool read_single(std::string& ref) { if (!skip_space()) return false; ref = ""; while (true) { char c = top(); if (c <= ' ') break; ref += c; st++; } return true; } bool read_single(double& ref) { std::string s; if (!read_single(s)) return false; ref = std::stod(s); return true; } template <class T, internal::is_signed_int_t<T>* = nullptr> bool read_single(T& sref) { using U = internal::to_unsigned_t<T>; if (!skip_space(50)) return false; bool neg = false; if (line[st] == '-') { neg = true; st++; } U ref = 0; do { ref = 10 * ref + (line[st++] & 0x0f); } while (line[st] >= '0'); sref = neg ? -ref : ref; return true; } template <class U, internal::is_unsigned_int_t<U>* = nullptr> bool read_single(U& ref) { if (!skip_space(50)) return false; ref = 0; do { ref = 10 * ref + (line[st++] & 0x0f); } while (line[st] >= '0'); return true; } int fd = -1; char line[SIZE]; size_t st = 0, ed = 0; bool eof = false; bool reread() { if (ed - st >= 50) return true; if (st > SIZE / 2) { std::memmove(line, line + st, ed - st); ed -= st; st = 0; } if (eof) return false; auto u = ::read(fd, line + ed, SIZE - ed); if (u == 0) { eof = true; line[ed] = '\0'; u = 1; } ed += u; return true; } char top() { if (st == ed) { bool f = reread(); assert(f); } return line[st]; } bool skip_space(unsigned int token_len = 0) { while (true) { while (st != ed && line[st] <= ' ') st++; if (ed - st > token_len) return true; for (auto i = st; i < ed; i++) { if (line[i] <= ' ') return true; } if (!reread()) return false; } } }; struct Printer { public: template <bool F = false> void write() {} template <bool F = false, class H, class... T> void write(const H& h, const T&... t) { if (F) write_single(' '); write_single(h); write<true>(t...); } template <class... T> void writeln(const T&... t) { write(t...); write_single('\n'); } Printer(FILE* _fp) : fd(fileno(_fp)) {} ~Printer() { flush(); } void flush() { ::write(fd, line, pos); pos = 0; } private: static std::array<std::array<char, 2>, 100> small; static std::array<unsigned long long, 20> tens; static int calc_len(unsigned long long x) { int i = (bsr(x) * 3 + 3) / 10; if (x < tens[i]) return i; else return i + 1; } static constexpr size_t SIZE = 1 << 15; int fd; char line[SIZE]; size_t pos = 0; void write_single(const char& val) { if (pos == SIZE) flush(); line[pos++] = val; } template <class T, internal::is_signed_int_t<T>* = nullptr> void write_single(const T& val) { using U = internal::to_unsigned_t<T>; if (val == 0) { write_single('0'); return; } if (pos > SIZE - 50) flush(); U uval = val; if (val < 0) { write_single('-'); uval = -uval; } write_unsigned(uval); } template <class U, internal::is_unsigned_int_t<U>* = nullptr> void write_single(U uval) { if (uval == 0) { write_single('0'); return; } if (pos > SIZE - 50) flush(); write_unsigned(uval); } template <class U, internal::is_unsigned_int_t<U>* = nullptr, std::enable_if_t<sizeof(U) == 4>* = nullptr> void write_unsigned(U uval) { write_unsigned(uint64_t(uval)); } template <class U, internal::is_unsigned_int_t<U>* = nullptr, std::enable_if_t<sizeof(U) == 8>* = nullptr> void write_unsigned(U uval) { size_t len = calc_len(uval); pos += len; char* ptr = line + pos; while (uval >= 100) { ptr -= 2; memcpy(ptr, small[uval % 100].data(), 2); uval /= 100; } if (uval >= 10) { memcpy(ptr - 2, small[uval].data(), 2); } else { *(ptr - 1) = char('0' + uval); } } void write_single(const std::string& s) { for (char c : s) write_single(c); } void write_single(const char* s) { size_t len = strlen(s); for (size_t i = 0; i < len; i++) write_single(s[i]); } template <class T> void write_single(const std::vector<T>& val) { auto n = val.size(); for (size_t i = 0; i < n; i++) { if (i) write_single(' '); write_single(val[i]); } } }; std::array<std::array<char, 2>, 100> Printer::small = [] { std::array<std::array<char, 2>, 100> table; for (int i = 0; i <= 99; i++) { table[i][1] = char('0' + (i % 10)); table[i][0] = char('0' + (i / 10 % 10)); } return table; }(); std::array<unsigned long long, 20> Printer::tens = [] { std::array<unsigned long long, 20> table; for (int i = 0; i < 20; i++) { table[i] = 1; for (int j = 0; j < i; j++) { table[i] *= 10; } } return table; }(); } // namespace yosupo using namespace yosupo; using mint = atcoder::modint998244353; #include <algorithm> #include <array> #include <bitset> #include <cassert> #include <complex> #include <cstdio> #include <cstring> #include <iostream> #include <map> #include <numeric> #include <queue> #include <set> #include <string> #include <unordered_map> #include <unordered_set> #include <vector> using namespace std; using uint = unsigned int; using ll = long long; using ull = unsigned long long; constexpr ll TEN(int n) { return (n == 0) ? 1 : 10 * TEN(n - 1); } template <class T> using V = vector<T>; template <class T> using VV = V<V<T>>; #ifdef LOCAL ostream& operator<<(ostream& os, __int128_t x) { if (x < 0) { os << "-"; x *= -1; } if (x == 0) { return os << "0"; } string s; while (x) { s += char(x % 10 + '0'); x /= 10; } reverse(s.begin(), s.end()); return os << s; } ostream& operator<<(ostream& os, __uint128_t x) { if (x == 0) { return os << "0"; } string s; while (x) { s += char(x % 10 + '0'); x /= 10; } reverse(s.begin(), s.end()); return os << s; } template <class T, class U> ostream& operator<<(ostream& os, const pair<T, U>& p); template <class T> ostream& operator<<(ostream& os, const V<T>& v); template <class T> ostream& operator<<(ostream& os, const deque<T>& v); template <class T, size_t N> ostream& operator<<(ostream& os, const array<T, N>& a); template <class T> ostream& operator<<(ostream& os, const set<T>& s); template <class T, class U> ostream& operator<<(ostream& os, const map<T, U>& m); template <class T, class U> ostream& operator<<(ostream& os, const pair<T, U>& p) { return os << "P(" << p.first << ", " << p.second << ")"; } template <class T> ostream& operator<<(ostream& os, const V<T>& v) { os << "["; bool f = false; for (auto d : v) { if (f) os << ", "; f = true; os << d; } return os << "]"; } template <class T> ostream& operator<<(ostream& os, const deque<T>& v) { os << "["; bool f = false; for (auto d : v) { if (f) os << ", "; f = true; os << d; } return os << "]"; } template <class T, size_t N> ostream& operator<<(ostream& os, const array<T, N>& a) { os << "["; bool f = false; for (auto d : a) { if (f) os << ", "; f = true; os << d; } return os << "]"; } template <class T> ostream& operator<<(ostream& os, const set<T>& s) { os << "{"; bool f = false; for (auto d : s) { if (f) os << ", "; f = true; os << d; } return os << "}"; } template <class T, class U> ostream& operator<<(ostream& os, const map<T, U>& s) { os << "{"; bool f = false; for (auto p : s) { if (f) os << ", "; f = true; os << p.first << ": " << p.second; } return os << "}"; } struct PrettyOS { ostream& os; bool first; template <class T> auto operator<<(T&& x) { if (!first) os << ", "; first = false; os << x; return *this; } }; template <class... T> void dbg0(T&&... t) { (PrettyOS{cerr, true} << ... << t); } #define dbg(...) \ do { \ cerr << __LINE__ << " : " << #__VA_ARGS__ << " = "; \ dbg0(__VA_ARGS__); \ cerr << endl; \ } while (false); #else #define dbg(...) #endif Scanner sc = Scanner(stdin); Printer pr = Printer(stdout); int main() { int n; sc.read(n); V<int> a(n); for (int i = 0; i < n; i++) { sc.read(a[i]); } mint result = 0; int ans = 0; for (int i = 1; i < n; i++) { ans = max(ans, a[i] - a[i - 1]); } mint bk = 0; for (; ans <= 2525; ans++) { V<mint> dp(n); dp[n - 1] = 2; int j = n - 1; mint buf = dp[n - 1]; for (int i = n - 3; i >= 0; i--) { // dp[i + 1] += dp[i + 2] + ... dp[j] while (i + 2 <= j && a[j] - a[i] > ans) { buf -= dp[j]; j--; } dp[i + 1] += buf; buf += buf; } mint sum = 0; for (auto x: dp) sum += x; result += (sum - bk) * ans; bk = sum; } pr.writeln(result.val()); return 0; }