#include #define f first #define s second using namespace std; using ll = long long; using ii = pair; constexpr int MX = 125; using ll = long long; using db = long double; // or double, if TL is tight using str = string; // yay python! using pi = pair; using pl = pair; using pd = pair; using vi = vector; using vb = vector; using vl = vector; using vd = vector; using vs = vector; using vpi = vector; using vpl = vector; using vpd = vector; #define tcT template using V = vector; tcT, size_t SZ> using AR = array; tcT> using PR = pair; // pairs #define mp make_pair #define f first #define s second // vectors // oops size(x), rbegin(x), rend(x) need C++17 #define sz(x) int((x).size()) #define bg(x) begin(x) #define all(x) bg(x), end(x) #define rall(x) x.rbegin(), x.rend() #define sor(x) sort(all(x)) #define rsz resize #define ins insert #define ft front() #define bk back() #define pb push_back #define eb emplace_back #define pf push_front #define rtn return #define lb lower_bound #define ub upper_bound tcT> int lwb(V& a, const T& b) { return int(lb(all(a),b)-bg(a)); } // loops #define FOR(i,a,b) for (int i = (a); i < (b); ++i) #define F0R(i,a) FOR(i,0,a) #define ROF(i,a,b) for (int i = (b)-1; i >= (a); --i) #define R0F(i,a) ROF(i,0,a) #define rep(a) F0R(_,a) #define each(a,x) for (auto& a: x) const int MOD = 1e9+7; // 998244353; const ll INF = 1e18; // not too close to LLONG_MAX const db PI = acos((db)-1); const int dx[4] = {1,0,-1,0}, dy[4] = {0,1,0,-1}; // for every grid problem!! mt19937 rng((uint32_t)chrono::steady_clock::now().time_since_epoch().count()); template using pqg = priority_queue,greater>; // bitwise ops // also see https://gcc.gnu.org/onlinedocs/gcc/Other-Builtins.html constexpr int pct(int x) { return __builtin_popcount(x); } // # of bits set constexpr int bits(int x) { // assert(x >= 0); // make C++11 compatible until USACO updates ... return x == 0 ? 0 : 31-__builtin_clz(x); } // floor(log2(x)) constexpr int p2(int x) { return 1<0&&a%b); } // divide a by b rounded up ll fdiv(ll a, ll b) { return a/b-((a^b)<0&&a%b); } // divide a by b rounded down tcT> bool ckmin(T& a, const T& b) { return b < a ? a = b, 1 : 0; } // set a = min(a,b) tcT> bool ckmax(T& a, const T& b) { return a < b ? a = b, 1 : 0; } tcTU> T fstTrue(T lo, T hi, U f) { hi ++; assert(lo <= hi); // assuming f is increasing while (lo < hi) { // find first index such that f is true T mid = lo+(hi-lo)/2; f(mid) ? hi = mid : lo = mid+1; } return lo; } tcTU> T lstTrue(T lo, T hi, U f) { lo --; assert(lo <= hi); // assuming f is decreasing while (lo < hi) { // find first index such that f is true T mid = lo+(hi-lo+1)/2; f(mid) ? lo = mid : hi = mid-1; } return lo; } tcT> void remDup(vector& v) { // sort and remove duplicates sort(all(v)); v.erase(unique(all(v)),end(v)); } tcTU> void erase(T& t, const U& u) { // don't erase auto it = t.find(u); assert(it != end(t)); t.erase(it); } // element that doesn't exist from (multi)set #define tcTUU tcT, class ...U inline namespace Helpers { //////////// is_iterable // https://stackoverflow.com/questions/13830158/check-if-a-variable-type-is-iterable // this gets used only when we can call begin() and end() on that type tcT, class = void> struct is_iterable : false_type {}; tcT> struct is_iterable())), decltype(end(declval())) > > : true_type {}; tcT> constexpr bool is_iterable_v = is_iterable::value; //////////// is_readable tcT, class = void> struct is_readable : false_type {}; tcT> struct is_readable> declval()), istream&> > > : true_type {}; tcT> constexpr bool is_readable_v = is_readable::value; //////////// is_printable // // https://nafe.es/posts/2020-02-29-is-printable/ tcT, class = void> struct is_printable : false_type {}; tcT> struct is_printable()), ostream&> > > : true_type {}; tcT> constexpr bool is_printable_v = is_printable::value; } inline namespace Input { tcT> constexpr bool needs_input_v = !is_readable_v && is_iterable_v; tcTUU> void re(T& t, U&... u); tcTU> void re(pair& p); // pairs // re: read tcT> typename enable_if,void>::type re(T& x) { cin >> x; } // default tcT> void re(complex& c) { T a,b; re(a,b); c = {a,b}; } // complex tcT> typename enable_if,void>::type re(T& i); // ex. vectors, arrays tcTU> void re(pair& p) { re(p.f,p.s); } tcT> typename enable_if,void>::type re(T& i) { each(x,i) re(x); } tcTUU> void re(T& t, U&... u) { re(t); re(u...); } // read multiple // rv: resize and read vectors void rv(size_t) {} tcTUU> void rv(size_t N, V& t, U&... u); template void rv(size_t, size_t N2, U&... u); tcTUU> void rv(size_t N, V& t, U&... u) { t.rsz(N); re(t); rv(N,u...); } template void rv(size_t, size_t N2, U&... u) { rv(N2,u...); } // dumb shortcuts to read in ints void decrement() {} // subtract one from each tcTUU> void decrement(T& t, U&... u) { --t; decrement(u...); } #define ints(...) int __VA_ARGS__; re(__VA_ARGS__); #define int1(...) ints(__VA_ARGS__); decrement(__VA_ARGS__); } inline namespace ToString { tcT> constexpr bool needs_output_v = !is_printable_v && is_iterable_v; // ts: string representation to print tcT> typename enable_if,str>::type ts(T v) { stringstream ss; ss << fixed << setprecision(15) << v; return ss.str(); } // default tcT> str bit_vec(T t) { // bit vector to string str res = "{"; F0R(i,sz(t)) res += ts(t[i]); res += "}"; return res; } str ts(V v) { return bit_vec(v); } template str ts(bitset b) { return bit_vec(b); } // bit vector tcTU> str ts(pair p); // pairs tcT> typename enable_if,str>::type ts(T v); // vectors, arrays tcTU> str ts(pair p) { return "("+ts(p.f)+", "+ts(p.s)+")"; } tcT> typename enable_if,str>::type ts_sep(T v, str sep) { // convert container to string w/ separator sep bool fst = 1; str res = ""; for (const auto& x: v) { if (!fst) res += sep; fst = 0; res += ts(x); } return res; } tcT> typename enable_if,str>::type ts(T v) { return "{"+ts_sep(v,", ")+"}"; } // for nested DS template typename enable_if,vs>::type ts_lev(const T& v) { return {ts(v)}; } template typename enable_if,vs>::type ts_lev(const T& v) { if (lev == 0 || !sz(v)) return {ts(v)}; vs res; for (const auto& t: v) { if (sz(res)) res.bk += ","; vs tmp = ts_lev(t); res.ins(end(res),all(tmp)); } F0R(i,sz(res)) { str bef = " "; if (i == 0) bef = "{"; res[i] = bef+res[i]; } res.bk += "}"; return res; } } inline namespace Output { template void pr_sep(ostream& os, str, const T& t) { os << ts(t); } template void pr_sep(ostream& os, str sep, const T& t, const U&... u) { pr_sep(os,sep,t); os << sep; pr_sep(os,sep,u...); } // print w/ no spaces template void pr(const T&... t) { pr_sep(cout,"",t...); } // print w/ spaces, end with newline void ps() { cout << "\n"; } template void ps(const T&... t) { pr_sep(cout," ",t...); ps(); } // debug to cerr template void dbg_out(const T&... t) { pr_sep(cerr," | ",t...); cerr << endl; } void loc_info(int line, str names) { cerr << "Line(" << line << ") -> [" << names << "]: "; } template void dbgl_out(const T& t) { cerr << "\n\n" << ts_sep(ts_lev(t),"\n") << "\n" << endl; } #ifdef LOCAL #define dbg(...) loc_info(__LINE__,#__VA_ARGS__), dbg_out(__VA_ARGS__) #define dbgl(lev,x) loc_info(__LINE__,#x), dbgl_out(x) #else // don't actually submit with this #define dbg(...) 0 #define dbgl(lev,x) 0 #endif } inline namespace FileIO { void setIn(str s) { freopen(s.c_str(),"r",stdin); } void setOut(str s) { freopen(s.c_str(),"w",stdout); } void setIO(str s = "") { cin.tie(0)->sync_with_stdio(0); // unsync C / C++ I/O streams // cin.exceptions(cin.failbit); // throws exception when do smth illegal // ex. try to read letter into int if (sz(s)) setIn(s+".in"), setOut(s+".out"); // for old USACO } } // make sure to intialize ALL GLOBAL VARS between tcs! /** * Description: Big Integer * Source: https://github.com/indy256/codelibrary/blob/master/cpp/numeric/bigint.cpp * oops that one uses FFT instead of Karatsuba now .... * Verification: https://oj.uz/problem/view/IOI11_parrots */ // base and base_digits must be consistent const int base = 1e9, base_digits = 9; struct bigint { // value == 0 is represented by empty z vi z; // digits int sign; // sign == 1 <==> value >= 0 bigint() : sign(1) {} // sign == -1 <==> value < 0 bigint(ll v) { *this = v; } bigint &operator=(ll v) { sign = v < 0 ? -1 : 1; v *= sign; // make v positive z.clear(); for (;v;v/=base) z.pb(v%base); return *this; } bigint(const str &s) { read(s); } // add char by char bigint &operator+=(const bigint &other) { //dbg("ADDING",*this,other,sign,other.sign); if (sign == other.sign) { for (int i = 0, carry = 0; i < sz(other.z) || carry; ++i) { if (i == sz(z)) z.pb(0); z[i] += carry+(i= base; if (carry) z[i] -= base; } } else if (other != 0 /* prevent infinite loop */) *this -= -other; return *this; } friend bigint operator+(bigint a, const bigint &b) { return a += b; } bigint &operator-=(const bigint &other) { if (sign == other.sign) { if ((sign == 1 && *this >= other) || (sign == -1 && *this <= other)) { for (int i = 0, carry = 0; i < sz(other.z) || carry; ++i) { z[i] -= carry+(isign = -this->sign; } } else *this += -other; return *this; } friend bigint operator-(bigint a, const bigint &b) { return a -= b; } bigint &operator*=(int v) { // oops make sure not to multiply by ll ... if (v < 0) sign = -sign, v = -v; for (int i = 0, carry = 0; i < sz(z) || carry; ++i) { if (i == sz(z)) z.pb(0); ll cur = (ll)z[i]*v+carry; carry = cur/base; z[i] = cur%base; } trim(); return *this; } bigint operator*(int v) const { return bigint(*this) *= v; } friend pair divmod(const bigint &a1, const bigint &b1) { int norm = base/(b1.z.bk+1); bigint a = a1.abs()*norm, b = b1.abs()*norm, q, r; // make last element of b big q.z.rsz(sz(a.z)); R0F(i,sz(a.z)) { r *= base; r += a.z[i]; int s1 = sz(b.z) < sz(r.z) ? r.z[sz(b.z)] : 0; int s2 = sz(b.z)-1 < sz(r.z) ? r.z[sz(b.z)-1] : 0; int d = ((ll)s1*base+s2)/b.z.bk; // best approximation r -= b*d; while (r < 0) r += b, --d; q.z[i] = d; } q.sign = a1.sign*b1.sign; r.sign = a1.sign; q.trim(); r.trim(); return {q,r/norm}; } friend bigint sqrt(const bigint &a1) { bigint a = a1; while (!sz(a.z) || sz(a.z)&1) a.z.pb(0); int n = sz(a.z), firstDigit = ::sqrt((db)a.z[n-1]*base+a.z[n-2]); int norm = base/(firstDigit+1); a *= norm; a *= norm; while (!sz(a.z) || sz(a.z)&1) a.z.pb(0); bigint r = (ll)a.z[n-1]*base+a.z[n-2]; firstDigit = (int)::sqrt((db)a.z[n-1]*base+a.z[n-2]); int q = firstDigit; bigint res; R0F(j,n/2) { for (;; --q) { bigint r1 = (r-(res*2*base+q)*q)*base*base + (j>0?(ll)a.z[2*j-1]*base+a.z[2*j-2]:0); if (r1 >= 0) { r = r1; break; } } res *= base; res += q; // add a bit to sqrt if (j > 0) { int d1 = sz(res.z)+2 < sz(r.z) ? r.z[sz(res.z)+2] : 0; // always 0/1? int d2 = sz(res.z)+1 < sz(r.z) ? r.z[sz(res.z)+1] : 0; int d3 = sz(res.z) < sz(r.z) ? r.z[sz(res.z)] : 0; q = ((ll) d1*base*base+(ll)d2*base+d3)/(firstDigit*2); } } res.trim(); return res/norm; } bigint operator/(const bigint &v) const { return divmod(*this, v).f; } bigint operator%(const bigint &v) const { return divmod(*this, v).s; } bigint &operator/=(int v) { if (v < 0) sign = -sign, v = -v; for (int i = sz(z)-1, rem = 0; i >= 0; --i) { ll cur = z[i]+rem*(ll)base; z[i] = cur/v; rem = cur%v; } trim(); return *this; } bigint operator/(int v) const { return bigint(*this) /= v; } int operator%(int v) const { if (v < 0) v = -v; int m = 0; R0F(i,sz(z)) m = (z[i]+m*(ll)base)%v; return m*sign; } bigint &operator*=(const bigint &v) { return *this = *this*v; } bigint &operator/=(const bigint &v) { return *this = *this/v; } bool operator<(const bigint &v) const { if (sign != v.sign) return sign < v.sign; if (sz(z) != sz(v.z)) return sz(z)*sign < sz(v.z) * v.sign; R0F(i,sz(z)) if (z[i] != v.z[i]) return z[i]*sign < v.z[i]*sign; return 0; // equal } bool operator>(const bigint &v) const { return v < *this; } bool operator<=(const bigint &v) const { return !(v < *this); } bool operator>=(const bigint &v) const { return !(*this < v); } bool operator==(const bigint &v) const { return !(*this < v) && !(v < *this); } bool operator!=(const bigint &v) const { return *this < v || v < *this; } void trim() { while (sz(z) && z.bk == 0) z.pop_back(); if (!sz(z)) sign = 1; // don't output -0 } bool isZero() const { return !sz(z); } friend bigint operator-(bigint v) { if (sz(v.z)) v.sign = -v.sign; return v; } bigint abs() const { return sign == 1 ? *this : -*this; } ll longValue() const { ll res = 0; R0F(i,sz(z)) res = res*base+z[i]; return res*sign; } friend bigint gcd(const bigint &a, const bigint &b) { return b.isZero() ? a : gcd(b, a % b); } // euclidean algo friend bigint lcm(const bigint &a, const bigint &b) { return a/gcd(a, b) * b; } void read(const str &s) { sign = 1; z.clear(); int pos = 0; while (pos < sz(s) && (s[pos] == '-' || s[pos] == '+')) { if (s[pos] == '-') sign = -sign; ++pos; } // account for sign for (int i = sz(s)-1; i >= pos; i -= base_digits) { int x = 0; for (int j = max(pos, i-base_digits+1); j <= i; j++) x = x*10+s[j]-'0'; z.pb(x); } trim(); } friend istream &operator>>(istream &is, bigint &v) { str s; is >> s; v.read(s); return is; } friend ostream &operator<<(ostream &os, const bigint &v) { if (v.sign == -1) os << '-'; os << (!sz(v.z) ? 0 : v.z.bk); R0F(i,sz(v.z)-1) os << setw(base_digits) << setfill('0') << v.z[i]; return os; // pad with zeroes } static vi convert_base(const vi &a, int old_digits, int new_digits) { vl p(max(old_digits, new_digits) + 1); // blocks of 10^{old} -> 10^{new} p[0] = 1; FOR(i,1,sz(p)) p[i] = p[i-1]*10; vi res; ll cur = 0; int cur_digits = 0; for (int v:a) { cur += v*p[cur_digits]; cur_digits += old_digits; while (cur_digits >= new_digits) { res.pb(cur%p[new_digits]); cur /= p[new_digits]; cur_digits -= new_digits; } } res.pb(cur); while (sz(res) && res.bk == 0) res.pop_back(); return res; } static vl karatMul(const vl &a, const vl &b) { // karatsuba int n = sz(a); vl res(2*n); if (n <= 32) { // naive multiply F0R(i,n) F0R(j,n) res[i+j] += a[i]*b[j]; return res; } int k = n/2; vl a1(begin(a),begin(a)+k), a2(k+all(a)); vl b1(begin(b),begin(b)+k), b2(k+all(b)); vl a1b1 = karatMul(a1, b1), a2b2 = karatMul(a2, b2); F0R(i,k) a2[i] += a1[i], b2[i] += b1[i]; vl r = karatMul(a2, b2); // three instead of four products F0R(i,sz(a1b1)) r[i] -= a1b1[i]; F0R(i,sz(a2b2)) r[i] -= a2b2[i]; F0R(i,sz(r)) res[i+k] += r[i]; F0R(i,sz(a1b1)) res[i] += a1b1[i]; F0R(i,sz(a2b2)) res[i+n] += a2b2[i]; return res; } bigint operator*(const bigint &v) const { if (min(sz(z),sz(v.z)) < 150) return mul_simple(v); bigint res; res.sign = sign*v.sign; // should work as long as # of digits isn't too large (> LLONG_MAX/10^{12}) vi a6 = convert_base(this->z, base_digits, 6); // blocks of 10^6 instead of 10^9 vi b6 = convert_base(v.z, base_digits, 6); vl a(all(a6)), b(all(b6)); while (sz(a) < sz(b)) a.pb(0); while (sz(b) < sz(a)) b.pb(0); while (sz(a)&(sz(a)-1)) a.pb(0), b.pb(0); // make size power of 2 vl c = karatMul(a, b); ll cur = 0; F0R(i,sz(c)) { // process carries cur += c[i]; res.z.pb(cur%1000000); cur /= 1000000; } res.z = convert_base(res.z,6,base_digits); res.trim(); return res; } bigint mul_simple(const bigint &v) const { bigint res; res.sign = sign*v.sign; res.z.rsz(sz(z)+sz(v.z)); F0R(i,sz(z)) if (z[i]) { ll cur = 0; for (int j = 0; j < sz(v.z) || cur; ++j) { cur += res.z[i+j]+(ll)z[i]*(j> s; return s; } };