結果

問題 No.1504 ヌメロニム
ユーザー maroon_kurimaroon_kuri
提出日時 2021-05-07 21:31:06
言語 C++17
(gcc 12.3.0 + boost 1.83.0)
結果
AC  
実行時間 195 ms / 2,000 ms
コード長 17,364 bytes
コンパイル時間 3,143 ms
コンパイル使用メモリ 229,300 KB
実行使用メモリ 45,000 KB
最終ジャッジ日時 2023-10-13 12:28:10
合計ジャッジ時間 12,103 ms
ジャッジサーバーID
(参考情報)
judge13 / judge11
このコードへのチャレンジ(β)

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 32 ms
28,036 KB
testcase_01 AC 31 ms
28,168 KB
testcase_02 AC 32 ms
28,036 KB
testcase_03 AC 31 ms
28,004 KB
testcase_04 AC 32 ms
27,988 KB
testcase_05 AC 32 ms
27,984 KB
testcase_06 AC 32 ms
27,952 KB
testcase_07 AC 31 ms
28,116 KB
testcase_08 AC 32 ms
28,104 KB
testcase_09 AC 32 ms
28,000 KB
testcase_10 AC 32 ms
27,988 KB
testcase_11 AC 32 ms
28,192 KB
testcase_12 AC 32 ms
28,180 KB
testcase_13 AC 31 ms
27,956 KB
testcase_14 AC 31 ms
28,048 KB
testcase_15 AC 31 ms
28,040 KB
testcase_16 AC 31 ms
28,232 KB
testcase_17 AC 31 ms
27,988 KB
testcase_18 AC 31 ms
27,960 KB
testcase_19 AC 32 ms
27,984 KB
testcase_20 AC 33 ms
28,292 KB
testcase_21 AC 32 ms
28,036 KB
testcase_22 AC 33 ms
28,164 KB
testcase_23 AC 32 ms
28,176 KB
testcase_24 AC 194 ms
44,628 KB
testcase_25 AC 113 ms
37,348 KB
testcase_26 AC 194 ms
44,864 KB
testcase_27 AC 113 ms
37,984 KB
testcase_28 AC 113 ms
38,012 KB
testcase_29 AC 192 ms
44,808 KB
testcase_30 AC 193 ms
44,716 KB
testcase_31 AC 112 ms
37,656 KB
testcase_32 AC 113 ms
38,048 KB
testcase_33 AC 191 ms
44,744 KB
testcase_34 AC 50 ms
30,180 KB
testcase_35 AC 50 ms
29,780 KB
testcase_36 AC 111 ms
36,172 KB
testcase_37 AC 41 ms
28,944 KB
testcase_38 AC 195 ms
45,000 KB
testcase_39 AC 192 ms
44,876 KB
testcase_40 AC 194 ms
44,864 KB
testcase_41 AC 191 ms
44,872 KB
testcase_42 AC 191 ms
44,892 KB
testcase_43 AC 192 ms
44,812 KB
testcase_44 AC 193 ms
44,768 KB
testcase_45 AC 192 ms
44,784 KB
testcase_46 AC 194 ms
44,864 KB
testcase_47 AC 195 ms
44,916 KB
testcase_48 AC 112 ms
37,520 KB
testcase_49 AC 111 ms
37,300 KB
testcase_50 AC 33 ms
28,120 KB
testcase_51 AC 32 ms
28,068 KB
testcase_52 AC 31 ms
28,092 KB
testcase_53 AC 32 ms
28,116 KB
testcase_54 AC 31 ms
27,988 KB
testcase_55 AC 50 ms
29,760 KB
testcase_56 AC 32 ms
28,172 KB
testcase_57 AC 32 ms
28,004 KB
testcase_58 AC 32 ms
28,044 KB
testcase_59 AC 32 ms
27,948 KB
testcase_60 AC 31 ms
28,024 KB
権限があれば一括ダウンロードができます

ソースコード

diff #

#include <bits/stdc++.h>
using namespace std;

using ll=long long;
#define int ll

#define rng(i,a,b) for(int i=int(a);i<int(b);i++)
#define rep(i,b) rng(i,0,b)
#define gnr(i,a,b) for(int i=int(b)-1;i>=int(a);i--)
#define per(i,b) gnr(i,0,b)
#define pb push_back
#define eb emplace_back
#define a first
#define b second
#define bg begin()
#define ed end()
#define all(x) x.bg,x.ed
#define si(x) int(x.size())
#ifdef LOCAL
#define dmp(x) cerr<<__LINE__<<" "<<#x<<" "<<x<<endl
#else
#define dmp(x) void(0)
#endif

template<class t,class u> bool chmax(t&a,u b){if(a<b){a=b;return true;}else return false;}
template<class t,class u> bool chmin(t&a,u b){if(b<a){a=b;return true;}else return false;}

template<class t> using vc=vector<t>;
template<class t> using vvc=vc<vc<t>>;

using pi=pair<int,int>;
using vi=vc<int>;

template<class t,class u>
ostream& operator<<(ostream& os,const pair<t,u>& p){
	return os<<"{"<<p.a<<","<<p.b<<"}";
}

template<class t> ostream& operator<<(ostream& os,const vc<t>& v){
	os<<"{";
	for(auto e:v)os<<e<<",";
	return os<<"}";
}

#define mp make_pair
#define mt make_tuple
#define one(x) memset(x,-1,sizeof(x))
#define zero(x) memset(x,0,sizeof(x))
#ifdef LOCAL
void dmpr(ostream&os){os<<endl;}
template<class T,class... Args>
void dmpr(ostream&os,const T&t,const Args&... args){
	os<<t<<" ";
	dmpr(os,args...);
}
#define dmp2(...) dmpr(cerr,__LINE__,##__VA_ARGS__)
#else
#define dmp2(...) void(0)
#endif

using uint=unsigned;
using ull=unsigned long long;

template<class t,size_t n>
ostream& operator<<(ostream&os,const array<t,n>&a){
	return os<<vc<t>(all(a));
}

template<int i,class T>
void print_tuple(ostream&,const T&){
}

template<int i,class T,class 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<class ...Args>
ostream& operator<<(ostream&os,const tuple<Args...>&t){
	os<<"{";
	print_tuple<0,tuple<Args...>,Args...>(os,t);
	return os<<"}";
}

template<class t>
void print(t x,int suc=1){
	cout<<x;
	if(suc==1)
		cout<<"\n";
	if(suc==2)
		cout<<" ";
}

ll read(){
	ll i;
	cin>>i;
	return i;
}

vi readvi(int n,int off=0){
	vi v(n);
	rep(i,n)v[i]=read()+off;
	return v;
}

pi readpi(int off=0){
	int a,b;cin>>a>>b;
	return pi(a+off,b+off);
}

template<class t,class u>
void print(const pair<t,u>&p,int suc=1){
	print(p.a,2);
	print(p.b,suc);
}

template<class T>
void print(const vector<T>&v,int suc=1){
	rep(i,v.size())
		print(v[i],i==int(v.size())-1?suc:2);
}

string readString(){
	string s;
	cin>>s;
	return s;
}

template<class T>
T sq(const T& t){
	return t*t;
}

//#define CAPITAL
void yes(bool ex=true){
	#ifdef CAPITAL
	cout<<"YES"<<"\n";
	#else
	cout<<"Yes"<<"\n";
	#endif
	if(ex)exit(0);
	#ifdef LOCAL
	cout.flush();
	#endif
}
void no(bool ex=true){
	#ifdef CAPITAL
	cout<<"NO"<<"\n";
	#else
	cout<<"No"<<"\n";
	#endif
	if(ex)exit(0);
	#ifdef LOCAL
	cout.flush();
	#endif
}
void possible(bool ex=true){
	#ifdef CAPITAL
	cout<<"POSSIBLE"<<"\n";
	#else
	cout<<"Possible"<<"\n";
	#endif
	if(ex)exit(0);
	#ifdef LOCAL
	cout.flush();
	#endif
}
void impossible(bool ex=true){
	#ifdef CAPITAL
	cout<<"IMPOSSIBLE"<<"\n";
	#else
	cout<<"Impossible"<<"\n";
	#endif
	if(ex)exit(0);
	#ifdef LOCAL
	cout.flush();
	#endif
}

constexpr ll ten(int n){
	return n==0?1:ten(n-1)*10;
}

const ll infLL=LLONG_MAX/3;

#ifdef int
const int inf=infLL;
#else
const int inf=INT_MAX/2-100;
#endif

int topbit(signed t){
	return t==0?-1:31-__builtin_clz(t);
}
int topbit(ll t){
	return t==0?-1:63-__builtin_clzll(t);
}
int botbit(signed a){
	return a==0?32:__builtin_ctz(a);
}
int botbit(ll a){
	return a==0?64:__builtin_ctzll(a);
}
int popcount(signed t){
	return __builtin_popcount(t);
}
int popcount(ll t){
	return __builtin_popcountll(t);
}
bool ispow2(int i){
	return i&&(i&-i)==i;
}
ll mask(int i){
	return (ll(1)<<i)-1;
}

bool inc(int a,int b,int c){
	return a<=b&&b<=c;
}

template<class t> void mkuni(vc<t>&v){
	sort(all(v));
	v.erase(unique(all(v)),v.ed);
}

ll rand_int(ll l, ll r) { //[l, r]
	#ifdef LOCAL
	static mt19937_64 gen;
	#else
	static mt19937_64 gen(chrono::steady_clock::now().time_since_epoch().count());
	#endif
	return uniform_int_distribution<ll>(l, r)(gen);
}

template<class t>
void myshuffle(vc<t>&a){
	rep(i,si(a))swap(a[i],a[rand_int(0,i)]);
}

template<class t>
int lwb(const vc<t>&v,const t&a){
	return lower_bound(all(v),a)-v.bg;
}

vvc<int> readGraph(int n,int m){
	vvc<int> g(n);
	rep(i,m){
		int a,b;
		cin>>a>>b;
		//sc.read(a,b);
		a--;b--;
		g[a].pb(b);
		g[b].pb(a);
	}
	return g;
}

vvc<int> readTree(int n){
	return readGraph(n,n-1);
}

//mint107 は verify してねえ
//#define DYNAMIC_MOD

struct modinfo{uint mod,root;
#ifdef DYNAMIC_MOD
constexpr modinfo(uint m,uint r):mod(m),root(r),im(0){set_mod(m);}
ull im;
constexpr void set_mod(uint m){
	mod=m;
	im=ull(-1)/m+1;
}
uint product(uint a,uint b)const{
	ull z=ull(a)*b;
	uint x=((unsigned __int128)z*im)>>64;
	uint v=uint(z)-x*mod;
	return v<mod?v:v+mod;
}
#endif
};
template<modinfo const&ref>
struct modular{
	static constexpr uint const &mod=ref.mod;
	static modular root(){return modular(ref.root);}
	uint v;
	//modular(initializer_list<uint>ls):v(*ls.bg){}
	modular(ll vv=0){s(vv%mod+mod);}
	modular& s(uint vv){
		v=vv<mod?vv:vv-mod;
		return *this;
	}
	modular operator-()const{return modular()-*this;}
	modular& operator+=(const modular&rhs){return s(v+rhs.v);}
	modular&operator-=(const modular&rhs){return s(v+mod-rhs.v);}
	modular&operator*=(const modular&rhs){
		#ifndef DYNAMIC_MOD
		v=ull(v)*rhs.v%mod;
		#else
		v=ref.product(v,rhs.v);
		#endif
		return *this;
	}
	modular&operator/=(const modular&rhs){return *this*=rhs.inv();}
	modular operator+(const modular&rhs)const{return modular(*this)+=rhs;}
	modular operator-(const modular&rhs)const{return modular(*this)-=rhs;}
	modular operator*(const modular&rhs)const{return modular(*this)*=rhs;}
	modular operator/(const modular&rhs)const{return modular(*this)/=rhs;}
	modular pow(ll n)const{
		modular res(1),x(*this);
		while(n){
			if(n&1)res*=x;
			x*=x;
			n>>=1;
		}
		return res;
	}
	modular inv()const{return pow(mod-2);}
	/*modular inv()const{
		int x,y;
		int g=extgcd<ll>(v,mod,x,y);
		assert(g==1);
		if(x<0)x+=mod;
		return modular(x);
	}*/
	friend modular operator+(int x,const modular&y){
		return modular(x)+y;
	}
	friend modular operator-(int x,const modular&y){
		return modular(x)-y;
	}
	friend modular operator*(int x,const modular&y){
		return modular(x)*y;
	}
	friend modular operator/(int x,const modular&y){
		return modular(x)/y;
	}
	friend ostream& operator<<(ostream&os,const modular&m){
		return os<<m.v;
	}
	friend istream& operator>>(istream&is,modular&m){
		ll x;is>>x;
		m=modular(x);
		return is;
	}
	bool operator<(const modular&r)const{return v<r.v;}
	bool operator==(const modular&r)const{return v==r.v;}
	bool operator!=(const modular&r)const{return v!=r.v;}
	explicit operator bool()const{
		return v;
	}
};

#ifndef DYNAMIC_MOD
extern constexpr modinfo base{998244353,3};
//extern constexpr modinfo base{1000000007,0};
//modinfo base{1,0};
#ifdef USE_GOOD_MOD
static_assert(base.mod==998244353);
#endif
#else
modinfo base(1,0);
extern constexpr modinfo base107(1000000007,0);
using mint107=modular<base107>;
#endif
using mint=modular<base>;

const int vmax=(1<<21)+10;
mint fact[vmax],finv[vmax],invs[vmax];
void initfact(){
	fact[0]=1;
	rng(i,1,vmax){
		fact[i]=fact[i-1]*i;
	}
	finv[vmax-1]=fact[vmax-1].inv();
	for(int i=vmax-2;i>=0;i--){
		finv[i]=finv[i+1]*(i+1);
	}
	for(int i=vmax-1;i>=1;i--){
		invs[i]=finv[i]*fact[i-1];
	}
}
mint choose(int n,int k){
	return fact[n]*finv[n-k]*finv[k];
}
mint binom(int a,int b){
	return fact[a+b]*finv[a]*finv[b];
}
mint catalan(int n){
	return binom(n,n)-(n-1>=0?binom(n-1,n+1):0);
}

/*
const int vmax=110;
mint binbuf[vmax][vmax];
mint choose(int n,int k){
	return binbuf[n-k][k];
}
mint binom(int a,int b){
	return binbuf[a][b];
}
void initfact(){
	binbuf[0][0]=1;
	rep(i,vmax)rep(j,vmax){
		if(i)binbuf[i][j]+=binbuf[i-1][j];
		if(j)binbuf[i][j]+=binbuf[i][j-1];
	}
}
*/

#define USE_GOOD_MOD

//size of input must be a power of 2
//output of forward fmt is bit-reversed
//output elements are in the range [0,mod*4)
//input of inverse fmt should be bit-reversed
template<class mint>
void inplace_fmt(const int n,mint*const f,bool inv){
	static constexpr uint mod=mint::mod;
	static constexpr uint mod2=mod*2;
	static constexpr int L=30;
	static mint g[L],ig[L],p2[L];
	if(g[0].v==0){
		rep(i,L){
			mint w=-mint::root().pow(((mod-1)>>(i+2))*3);
			g[i]=w;
			ig[i]=w.inv();
			p2[i]=mint(1<<i).inv();
		}
	}
	if(!inv){
		int b=n;
		if(b>>=1){//input:[0,mod)
			rep(i,b){
				uint x=f[i+b].v;
				f[i+b].v=f[i].v+mod-x;
				f[i].v+=x;
			}
		}
		if(b>>=1){//input:[0,mod*2)
			mint p=1;
			for(int i=0,k=0;i<n;i+=b*2){
				rng(j,i,i+b){
					uint x=(f[j+b]*p).v;
					f[j+b].v=f[j].v+mod-x;
					f[j].v+=x;
				}
				p*=g[__builtin_ctz(++k)];
			}
		}
		while(b){
			if(b>>=1){//input:[0,mod*3)
				mint p=1;
				for(int i=0,k=0;i<n;i+=b*2){
					rng(j,i,i+b){
						uint x=(f[j+b]*p).v;
						f[j+b].v=f[j].v+mod-x;
						f[j].v+=x;
					}
					p*=g[__builtin_ctz(++k)];
				}
			}
			if(b>>=1){//input:[0,mod*4)
				mint p=1;
				for(int i=0,k=0;i<n;i+=b*2){
					rng(j,i,i+b){
						uint x=(f[j+b]*p).v;
						f[j].v=(f[j].v<mod2?f[j].v:f[j].v-mod2);
						f[j+b].v=f[j].v+mod-x;
						f[j].v+=x;
					}
					p*=g[__builtin_ctz(++k)];
				}
			}
		}
	}else{
		int b=1;
		if(b<n/2){//input:[0,mod)
			mint p=1;
			for(int i=0,k=0;i<n;i+=b*2){
				rng(j,i,i+b){
					ull x=f[j].v+mod-f[j+b].v;
					f[j].v+=f[j+b].v;
					f[j+b].v=x*p.v%mod;
				}
				p*=ig[__builtin_ctz(++k)];
			}
			b<<=1;
		}
		for(;b<n/2;b<<=1){
			mint p=1;
			for(int i=0,k=0;i<n;i+=b*2){
				rng(j,i,i+b/2){//input:[0,mod*2)
					ull x=f[j].v+mod2-f[j+b].v;
					f[j].v+=f[j+b].v;
					f[j].v=(f[j].v)<mod2?f[j].v:f[j].v-mod2;
					f[j+b].v=x*p.v%mod;
				}
				rng(j,i+b/2,i+b){//input:[0,mod)
					ull x=f[j].v+mod-f[j+b].v;
					f[j].v+=f[j+b].v;
					f[j+b].v=x*p.v%mod;
				}
				p*=ig[__builtin_ctz(++k)];
			}
		}
		if(b<n){//input:[0,mod*2)
			rep(i,b){
				uint x=f[i+b].v;
				f[i+b].v=f[i].v+mod2-x;
				f[i].v+=x;
			}
		}
		mint z=p2[__lg(n)];
		rep(i,n)f[i]*=z;
	}
}

template<class mint>
void inplace_fmt(vector<mint>&f,bool inv){
	inplace_fmt(si(f),f.data(),inv);
}

//size of input must be a power of 2
//output elements are in the range [0,mod*4)
template<class mint>
void half_fmt(const int n,mint*const f){
	static constexpr uint mod=mint::mod;
	static constexpr uint mod2=mod*2;
	static const int L=30;
	static mint g[L],h[L];
	if(g[0].v==0){
		rep(i,L){
			g[i]=-mint::root().pow(((mod-1)>>(i+2))*3);
			h[i]=mint::root().pow((mod-1)>>(i+2));
		}
	}
	int b=n;
	int lv=0;
	if(b>>=1){//input:[0,mod)
		mint p=h[lv++];
		for(int i=0,k=0;i<n;i+=b*2){
			rng(j,i,i+b){
				uint x=(f[j+b]*p).v;
				f[j+b].v=f[j].v+mod-x;
				f[j].v+=x;
			}
			p*=g[__builtin_ctz(++k)];
		}
	}
	if(b>>=1){//input:[0,mod*2)
		mint p=h[lv++];
		for(int i=0,k=0;i<n;i+=b*2){
			rng(j,i,i+b){
				uint x=(f[j+b]*p).v;
				f[j+b].v=f[j].v+mod-x;
				f[j].v+=x;
			}
			p*=g[__builtin_ctz(++k)];
		}
	}
	while(b){
		if(b>>=1){//input:[0,mod*3)
			mint p=h[lv++];
			for(int i=0,k=0;i<n;i+=b*2){
				rng(j,i,i+b){
					uint x=(f[j+b]*p).v;
					f[j+b].v=f[j].v+mod-x;
					f[j].v+=x;
				}
				p*=g[__builtin_ctz(++k)];
			}
		}
		if(b>>=1){//input:[0,mod*4)
			mint p=h[lv++];
			for(int i=0,k=0;i<n;i+=b*2){
				rng(j,i,i+b){
					uint x=(f[j+b]*p).v;
					f[j].v=(f[j].v<mod2?f[j].v:f[j].v-mod2);
					f[j+b].v=f[j].v+mod-x;
					f[j].v+=x;
				}
				p*=g[__builtin_ctz(++k)];
			}
		}
	}
}

template<class mint>
void half_fmt(vector<mint>&f){
	half_fmt(si(f),f.data());
}

#ifdef USE_GOOD_MOD

template<class mint>
vc<mint> multiply(vc<mint> x,const vc<mint>&y,bool same=false){
	int n=si(x)+si(y)-1;
	int s=1;
	while(s<n)s*=2;
	x.resize(s);inplace_fmt(x,false);
	if(!same){
		vc<mint> z(s);
		rep(i,si(y))z[i]=y[i];
		inplace_fmt(z,false);
		rep(i,s)x[i]*=z[i];
	}else{
		rep(i,s)x[i]*=x[i];
	}
	inplace_fmt(x,true);x.resize(n);
	return x;
}
template<class mint>
vc<mint> multiply_givenlength(vc<mint> x,const vc<mint>&y,bool same=false){
	int s=si(x);
	assert(ispow2(s));
	assert(si(y));
	x.resize(s);inplace_fmt(x,false);
	if(!same){
		vc<mint> z(s);
		rep(i,si(y))z[i]=y[i];
		inplace_fmt(z,false);
		rep(i,s)x[i]*=z[i];
	}else{
		rep(i,s)x[i]*=x[i];
	}
	inplace_fmt(x,true);
	return x;
}

#else

//59501818244292734739283969-1=5.95*10^25 までの値を正しく計算
//最終的な列の大きさが 2^24 までなら動く
//最終的な列の大きさが 2^20 以下のときは,下の 3 つの素数を使ったほうが速い(は?)
//VERIFY: yosupo
//Yukicoder No980 (same=true)
namespace arbitrary_convolution{
	constexpr modinfo base0{167772161,3};//2^25 * 5 + 1
	constexpr modinfo base1{469762049,3};//2^26 * 7 + 1
	constexpr modinfo base2{754974721,11};//2^24 * 45 + 1
	//extern constexpr modinfo base0{1045430273,3};//2^20 * 997 + 1
	//extern constexpr modinfo base1{1051721729,6};//2^20 * 1003 + 1
	//extern constexpr modinfo base2{1053818881,7};//2^20 * 1005 + 1
	using mint0=modular<base0>;
	using mint1=modular<base1>;
	using mint2=modular<base2>;
	template<class t,class mint>
	vc<t> sub(const vc<mint>&x,const vc<mint>&y,bool same=false){
		int n=si(x)+si(y)-1;
		int s=1;
		while(s<n)s*=2;
		vc<t> z(s);rep(i,si(x))z[i]=x[i].v;
		inplace_fmt(z,false);
		if(!same){
			vc<t> w(s);rep(i,si(y))w[i]=y[i].v;
			inplace_fmt(w,false);
			rep(i,s)z[i]*=w[i];
		}else{
			rep(i,s)z[i]*=z[i];
		}
		inplace_fmt(z,true);z.resize(n);
		return z;
	}
	template<class mint>
	vc<mint> multiply(const vc<mint>&x,const vc<mint>&y,bool same=false){
		auto d0=sub<mint0>(x,y,same);
		auto d1=sub<mint1>(x,y,same);
		auto d2=sub<mint2>(x,y,same);
		int n=si(d0);
		vc<mint> res(n);
		static const mint1 r01=mint1(mint0::mod).inv();
		static const mint2 r02=mint2(mint0::mod).inv();
		static const mint2 r12=mint2(mint1::mod).inv();
		static const mint2 r02r12=r02*r12;
		static const mint w1=mint(mint0::mod);
		static const mint w2=w1*mint(mint1::mod);
		rep(i,n){
			ull a=d0[i].v;
			ull b=(d1[i].v+mint1::mod-a)*r01.v%mint1::mod;
			ull c=((d2[i].v+mint2::mod-a)*r02r12.v+(mint2::mod-b)*r12.v)%mint2::mod;
			res[i].v=(a+b*w1.v+c*w2.v)%mint::mod;
		}
		return res;
	}
	template<class t,class mint>
	vc<t> sub_givenlength(const vc<mint>&x,const vc<mint>&y,bool same=false){
		int s=si(x);
		assert(ispow2(s));
		assert(si(y)==s);
		vc<t> z(s);rep(i,si(x))z[i]=x[i].v;
		inplace_fmt(z,false);
		if(!same){
			vc<t> w(s);rep(i,si(y))w[i]=y[i].v;
			inplace_fmt(w,false);
			rep(i,s)z[i]*=w[i];
		}else{
			rep(i,s)z[i]*=z[i];
		}
		inplace_fmt(z,true);
		return z;
	}
	template<class mint>
	vc<mint> multiply_givenlength(const vc<mint>&x,const vc<mint>&y,bool same=false){
		auto d0=sub_givenlength<mint0>(x,y,same);
		auto d1=sub_givenlength<mint1>(x,y,same);
		auto d2=sub_givenlength<mint2>(x,y,same);
		int n=si(d0);
		vc<mint> res(n);
		static const mint1 r01=mint1(mint0::mod).inv();
		static const mint2 r02=mint2(mint0::mod).inv();
		static const mint2 r12=mint2(mint1::mod).inv();
		static const mint2 r02r12=r02*r12;
		static const mint w1=mint(mint0::mod);
		static const mint w2=w1*mint(mint1::mod);
		rep(i,n){
			ull a=d0[i].v;
			ull b=(d1[i].v+mint1::mod-a)*r01.v%mint1::mod;
			ull c=((d2[i].v+mint2::mod-a)*r02r12.v+(mint2::mod-b)*r12.v)%mint2::mod;
			res[i].v=(a+b*w1.v+c*w2.v)%mint::mod;
		}
		return res;
	}
}
using arbitrary_convolution::multiply;
using arbitrary_convolution::multiply_givenlength;

#endif

namespace integer_convolution{
	extern constexpr modinfo base0{1045430273,3};//2^20 * 997 + 1
	extern constexpr modinfo base1{1051721729,6};//2^20 * 1003 + 1
	using mint0=modular<base0>;
	using mint1=modular<base1>;
	template<class t>
	vc<t> sub(const vi&x,const vi&y,bool same=false){
		int n=si(x)+si(y)-1;
		int s=1;
		while(s<n)s*=2;
		vc<t> z(s);rep(i,si(x))z[i]=x[i];
		inplace_fmt(z,false);
		if(!same){
			vc<t> w(s);rep(i,si(y))w[i]=y[i];
			inplace_fmt(w,false);
			rep(i,s)z[i]*=w[i];
		}else{
			rep(i,s)z[i]*=z[i];
		}
		inplace_fmt(z,true);z.resize(n);
		return z;
	}
	vi multiply(const vi&x,const vi&y,bool same=false){
		auto d0=sub<mint0>(x,y,same);
		auto d1=sub<mint1>(x,y,same);
		const mint1 r=mint1(mint0::mod).inv();
		int n=si(d0);
		vi res(n);
		rep(i,n){
			res[i]=d0[i].v+(r*(d1[i]-d0[i].v)).v*(ull)mint0::mod;
		}
		return res;
	}
}

//最大で 1<<mx のサイズの fft が登場!
template<class mint>
vc<mint> large_convolution(const vc<mint>&a,const vc<mint>&b,int mx){
	int n=si(a),m=si(b);
	vc<mint> c(n+m-1);
	int len=1<<(mx-1);
	for(int i=0;i<n;i+=len){
		for(int j=0;j<n;j+=len){
			int x=min(len,n-i),y=min(len,m-j);
			auto d=multiply(vc<mint>(a.bg+i,a.bg+i+x),vc<mint>(b.bg+j,b.bg+j+y));
			rep(k,si(d))
				c[i+j+k]+=d[k];
		}
	}
	return c;
}

void slv(){
	int n;cin>>n;
	string s;cin>>s;
	vc<mint> a(n),b(n);
	rep(i,n)if(s[i]=='i')a[i]=1;
	else b[n-1-i]=1;
	auto c=multiply(a,b);
	c.resize(n-1);
	rep(i,n-1)c[i]*=fact[n-2-i];
	vc<mint> d(n-1);
	rep(i,n-1)d[i]=finv[i];
	auto e=multiply(c,d);
	e.resize(n-1);
	reverse(all(e));
	rep(i,n-1)e[i]*=finv[i];
	int ans=0;
	rep(i,n-1)ans^=e[i].v;
	print(ans);
}

signed main(){
	cin.tie(0);
	ios::sync_with_stdio(0);
	cout<<fixed<<setprecision(20);
	
	initfact();
	//int t;cin>>t;rep(_,t)
	slv();
}
0