#pragma GCC optimize("Ofast") ///////////////////////////////////////////////////////// /** * Useful Macros * by subcrip * (requires C++17) */ #include #include using namespace std; using namespace __gnu_cxx; using namespace __gnu_pbds; /* macro helpers */ #define __NARGS(...) std::tuple_size::value #define __DECOMPOSE_S(a, x) auto x = a; #define __DECOMPOSE_N(a, ...) auto [__VA_ARGS__] = a; constexpr void __() {} #define __AS_PROCEDURE(...) __(); __VA_ARGS__; __() #define __as_typeof(container) decltype(container)::value_type /* type aliases */ using ll = int64_t; using ull = uint64_t; using pii = pair; using pil = pair; using pli = pair; using pll = pair; /* constants */ constexpr int INF = 0x3f3f3f3f; constexpr ull MDL = 1e9 + 7; constexpr ull PRIME = 998'244'353; constexpr ull MDL1 = 825; constexpr ull MDL2 = 87825; /* bit-wise operations */ #define lowbit(x) ((x) & -(x)) #define popcount(x) (__builtin_popcountll(ll(x))) #define parity(x) (__builtin_parityll(ll(x))) #define msp(x) (63LL - __builtin_clzll(ll(x))) #define lsp(x) (__builtin_ctzll(ll(x))) /* arithmetic operations */ #define mod(x, y) (((x) % (y) + (y)) % (y)) /* fast pairs */ #define upair ull #define umake(x, y) (ull(x) << 32 | (ull(y) & ((1ULL << 32) - 1))) #define u1(p) ((p) >> 32) #define u2(p) ((p) & ((1ULL << 32) - 1)) #define ult std::less #define ugt std::greater #define ipair ull #define imake(x, y) (umake(x, y)) #define i1(p) (int(u1(ll(p)))) #define i2(p) (ll(u2(p) << 32) >> 32) struct ilt { bool operator()(const ipair& a, const ipair& b) const { if (i1(a) == i1(b)) return i2(a) < i2(b); else return i1(a) < i1(b); } }; struct igt { bool operator()(const ipair& a, const ipair& b) const { if (i1(a) == i1(b)) return i2(a) > i2(b); else return i1(a) > i1(b); } }; /* conditions */ #define loop while (1) #define if_or(var, val) if (!(var == val)) var = val; else #define continue_or(var, val) __AS_PROCEDURE(if (var == val) continue; var = val;) #define break_or(var, val) __AS_PROCEDURE(if (var == val) break; var = val;) /* hash */ struct safe_hash { // https://codeforces.com/blog/entry/62393 static uint64_t splitmix64(uint64_t x) { // http://xorshift.di.unimi.it/splitmix64.c x += 0x9e3779b97f4a7c15; x = (x ^ (x >> 30)) * 0xbf58476d1ce4e5b9; x = (x ^ (x >> 27)) * 0x94d049bb133111eb; return x ^ (x >> 31); } size_t operator()(uint64_t x) const { static const uint64_t FIXED_RANDOM = chrono::steady_clock::now().time_since_epoch().count(); return splitmix64(x + FIXED_RANDOM); } }; struct pair_hash { template size_t operator()(const pair& a) const { auto hash1 = safe_hash()(a.first); auto hash2 = safe_hash()(a.second); if (hash1 != hash2) { return hash1 ^ hash2; } return hash1; } }; /* build data structures */ #define unordered_counter(from, to) __AS_PROCEDURE(unordered_map<__as_typeof(from), size_t, safe_hash> to; for (auto&& x : from) ++to[x];) #define counter(from, to, cmp) __AS_PROCEDURE(map<__as_typeof(from), size_t, cmp> to; for (auto&& x : from) ++to[x];) #define pa(a) __AS_PROCEDURE(__typeof(a) pa; pa.push_back({}); for (auto&&x : a) pa.push_back(pa.back() + x);) #define sa(a) __AS_PROCEDURE(__typeof(a) sa(a.size() + 1); {int n = a.size(); for (int i = n - 1; i >= 0; --i) sa[i] = sa[i + 1] + a[i];};) #define adj(ch, n) __AS_PROCEDURE(vector> ch((n) + 1);) #define edge(ch, u, v) __AS_PROCEDURE(ch[u].push_back(v), ch[v].push_back(u);) #define Edge(ch, u, v) __AS_PROCEDURE(ch[u].push_back(v);) /* io */ #define untie __AS_PROCEDURE(ios_base::sync_with_stdio(0), cin.tie(NULL)) template void __read(T& x) { cin >> x; } template void __read(T& x, U&... args) { cin >> x; __read(args...); } #define read(type, ...) __AS_PROCEDURE(type __VA_ARGS__; __read(__VA_ARGS__);) #define readvec(type, a, n) __AS_PROCEDURE(vector a(n); for (int i = 0; i < (n); ++i) cin >> a[i];) #define putvec(a) __AS_PROCEDURE(for (auto&& x : a) cout << x << ' '; cout << endl;) #define debug(x) __AS_PROCEDURE(cerr << #x" = " << (x) << endl;) #define debugvec(a) __AS_PROCEDURE(cerr << #a" = "; for (auto&& x : a) cerr << x << ' '; cerr << endl;) template ostream& operator<<(ostream& out, vector vec) { for (auto&& i : vec) out << i << ' '; return out; } /* pops */ #define poptop(q, ...) __AS_PROCEDURE(auto [__VA_ARGS__] = q.top(); q.pop();) #define popback(q, ...) __AS_PROCEDURE(auto [__VA_ARGS__] = q.back(); q.pop_back();) #define popfront(q, ...) __AS_PROCEDURE(auto [__VA_ARGS__] = q.front();q.pop_front();) /* math */ void __exgcd(ll a, ll b, ll& x, ll& y) { if (b == 0) { x = 1, y = 0; return; } __exgcd(b, a % b, y, x); y -= a / b * x; } ll inverse(ll a, ll b) { ll x, y; __exgcd(a, b, x, y); return mod(x, b); } /* string algorithms */ vector calc_next(string t) { // pi function of t int n = (int)t.length(); vector pi(n); for (int i = 1; i < n; i++) { int j = pi[i - 1]; while (j > 0 && t[i] != t[j]) j = pi[j - 1]; if (t[i] == t[j]) j++; pi[i] = j; } return pi; } vector calc_z(string t) { // z function of t int m = t.length(); vector z; z.push_back(m); pair prev = {1, -1}; for (int i = 1; i < m; ++i) { if (z[i - prev.first] + i <= prev.second) { z.push_back(z[i - prev.first]); } else { int j = max(i, prev.second + 1); while (j < m && t[j] == t[j - i]) ++j; z.push_back(j - i); prev = {i, j - 1}; } } return z; } vector kmp(string s, string t) { // find all t in s string cur = t + '#' + s; int sz1 = s.size(), sz2 = t.size(); vector v; vector lps = calc_next(cur); for (int i = sz2 + 1; i <= sz1 + sz2; i++) { if (lps[i] == sz2) v.push_back(i - 2 * sz2); } return v; } int period(string s) { // find the length of shortest recurring period int n = s.length(); auto z = calc_z(s); for (int i = 1; i <= n / 2; ++i) { if (n % i == 0 && z[i] == n - i) { return i; } } return n; } /////////////////////////////////////////////////////////