結果
| 問題 | No.2588 Increasing Record |
| ユーザー |
👑  Nachia
|
| 提出日時 | 2023-12-23 15:18:10 |
| 言語 | C++17 (gcc 12.3.0 + boost 1.83.0) |
| 結果 |
AC
|
| 実行時間 | 86 ms / 3,000 ms |
| コード長 | 23,327 bytes |
| コンパイル時間 | 1,497 ms |
| コンパイル使用メモリ | 117,008 KB |
| 実行使用メモリ | 18,540 KB |
| 最終ジャッジ日時 | 2024-09-27 12:24:25 |
| 合計ジャッジ時間 | 5,415 ms |
|
ジャッジサーバーID （参考情報） |
judge3 / judge1 |
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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 | 1 ms
6,816 KB |
| testcase_01 | AC | 2 ms
6,944 KB |
| testcase_02 | AC | 2 ms
6,940 KB |
| testcase_03 | AC | 1 ms
6,940 KB |
| testcase_04 | AC | 2 ms
6,944 KB |
| testcase_05 | AC | 2 ms
6,940 KB |
| testcase_06 | AC | 2 ms
6,940 KB |
| testcase_07 | AC | 1 ms
6,944 KB |
| testcase_08 | AC | 2 ms
6,944 KB |
| testcase_09 | AC | 2 ms
6,944 KB |
| testcase_10 | AC | 1 ms
6,940 KB |
| testcase_11 | AC | 2 ms
6,944 KB |
| testcase_12 | AC | 25 ms
8,320 KB |
| testcase_13 | AC | 28 ms
8,320 KB |
| testcase_14 | AC | 30 ms
8,320 KB |
| testcase_15 | AC | 27 ms
8,320 KB |
| testcase_16 | AC | 36 ms
8,832 KB |
| testcase_17 | AC | 53 ms
12,432 KB |
| testcase_18 | AC | 72 ms
15,084 KB |
| testcase_19 | AC | 80 ms
17,848 KB |
| testcase_20 | AC | 82 ms
18,376 KB |
| testcase_21 | AC | 83 ms
18,540 KB |
| testcase_22 | AC | 83 ms
18,408 KB |
| testcase_23 | AC | 84 ms
18,508 KB |
| testcase_24 | AC | 86 ms
18,408 KB |
| testcase_25 | AC | 60 ms
12,428 KB |
| testcase_26 | AC | 75 ms
15,084 KB |
| testcase_27 | AC | 81 ms
18,392 KB |
| testcase_28 | AC | 84 ms
18,328 KB |
| testcase_29 | AC | 82 ms
18,464 KB |
| testcase_30 | AC | 37 ms
12,428 KB |
| testcase_31 | AC | 45 ms
15,088 KB |
| testcase_32 | AC | 48 ms
17,808 KB |
| testcase_33 | AC | 49 ms
18,380 KB |
| testcase_34 | AC | 52 ms
18,416 KB |
| testcase_35 | AC | 50 ms
18,412 KB |
| testcase_36 | AC | 49 ms
18,536 KB |
| testcase_37 | AC | 80 ms
18,536 KB |
| testcase_38 | AC | 57 ms
12,428 KB |
| testcase_39 | AC | 68 ms
18,492 KB |
| testcase_40 | AC | 66 ms
18,408 KB |
| testcase_41 | AC | 68 ms
18,536 KB |
| testcase_42 | AC | 80 ms
18,412 KB |
| testcase_43 | AC | 78 ms
18,416 KB |
| testcase_44 | AC | 49 ms
12,360 KB |
| testcase_45 | AC | 51 ms
14,688 KB |
| testcase_46 | AC | 52 ms
17,816 KB |
ソースコード
#define NDEBUG
#include <atcoder/modint>
#include <atcoder/fenwicktree>
#include <vector>
#include <iterator>
#include <algorithm>
#include <functional>
#include <utility>
#include <string>
template<class Elem> struct vec;
template<class Iter>
struct seq_view{
using Ref = typename std::iterator_traits<Iter>::reference;
using Elem = typename std::iterator_traits<Iter>::value_type;
Iter a, b;
Iter begin() const { return a; }
Iter end() const { return b; }
int size() const { return (int)(b-a); }
seq_view(Iter first, Iter last) : a(first), b(last) {}
seq_view sort() const { std::sort(a, b); return *this; }
Ref& operator[](int x){ return *(a+x); }
template<class F = std::less<Elem>, class ret = vec<int>> ret sorti(F f = F()) const {
ret x(size()); for(int i=0; i<size(); i++) x[i] = i;
x().sort([&](int l, int r){ return f(a[l],a[r]); });
return x;
}
template<class ret = vec<Elem>> ret col() const { return ret(begin(), end()); }
template<class F = std::equal_to<Elem>, class ret = vec<std::pair<Elem, int>>>
ret rle(F eq = F()) const {
auto x = ret();
for(auto& a : (*this)){
if(x.size() == 0 || !eq(x[x.size()-1].first, a)) x.emp(a, 1); else x[x.size()-1].second++;
} return x;
}
template<class F> seq_view sort(F f) const { std::sort(a, b, f); return *this; }
Iter uni() const { return std::unique(a, b); }
Iter lb(const Elem& x) const { return std::lower_bound(a, b, x); }
Iter ub(const Elem& x) const { return std::upper_bound(a, b, x); }
int lbi(const Elem& x) const { return lb(x) - a; }
int ubi(const Elem& x) const { return ub(x) - a; }
seq_view bound(const Elem& l, const Elem& r) const { return { lb(l), lb(r) }; }
template<class F> Iter lb(const Elem& x, F f) const { return std::lower_bound(a, b, x, f); }
template<class F> Iter ub(const Elem& x, F f) const { return std::upper_bound(a, b, x, f); }
template<class F> Iter when_true_to_false(F f) const {
if(a == b) return a;
return std::lower_bound(a, b, *a,
[&](const Elem& x, const Elem&){ return f(x); });
}
seq_view same(Elem x) const { return { lb(x), ub(x) }; }
template<class F> auto map(F f) const {
vec<typename Iter::value_type> r;
for(auto& x : *this) r.emp(f(x));
return r;
}
Iter max() const { return std::max_element(a, b); }
Iter min() const { return std::min_element(a, b); }
template<class F = std::less<Elem>>
Iter min(F f) const { return std::min_element(a, b, f); }
seq_view rev() const { std::reverse(a, b); return *this; }
};
template<class Elem>
struct vec {
using Base = typename std::vector<Elem>;
using Iter = typename Base::iterator;
using CIter = typename Base::const_iterator;
using View = seq_view<Iter>;
using CView = seq_view<CIter>;
vec(){}
explicit vec(int n, const Elem& value = Elem()) : a(0<n?n:0, value) {}
template <class I2> vec(I2 first, I2 last) : a(first, last) {}
vec(std::initializer_list<Elem> il) : a(std::move(il)) {}
vec(Base b) : a(std::move(b)) {}
operator Base() const { return a; }
Iter begin(){ return a.begin(); }
CIter begin() const { return a.begin(); }
Iter end(){ return a.end(); }
CIter end() const { return a.end(); }
int size() const { return a.size(); }
bool empty() const { return a.empty(); }
Elem& back(){ return a.back(); }
const Elem& back() const { return a.back(); }
vec sortunied(){ vec x = *this; x().sort(); x.a.erase(x().uni(), x.end()); return x; }
Iter operator()(int x){ return a.begin() + x; }
CIter operator()(int x) const { return a.begin() + x; }
View operator()(int l, int r){ return { (*this)(l), (*this)(r) }; }
CView operator()(int l, int r) const { return { (*this)(l), (*this)(r) }; }
View operator()(){ return (*this)(0,size()); }
CView operator()() const { return (*this)(0,size()); }
Elem& operator[](int x){ return a[x]; }
const Elem& operator[](int x) const { return a[x]; }
Base& operator*(){ return a; }
const Base& operator*() const { return a; }
vec& push(Elem args){
a.push_back(std::move(args));
return *this;
}
template<class... Args>
vec& emp(Args &&... args){
a.emplace_back(std::forward<Args>(args) ...);
return *this;
}
template<class Range>
vec& app(Range& x){ for(auto& v : a) emp(v); }
Elem pop(){
Elem x = std::move(a.back());
a.pop_back(); return x;
}
bool operator==(const vec& r) const { return a == r.a; }
bool operator!=(const vec& r) const { return a != r.a; }
bool operator<(const vec& r) const { return a < r.a; }
bool operator<=(const vec& r) const { return a <= r.a; }
bool operator>(const vec& r) const { return a > r.a; }
bool operator>=(const vec& r) const { return a >= r.a; }
vec<vec<Elem>> pile(int n) const { return vec<vec<Elem>>(n, *this); }
template<class F> vec& filter(F f){
int p = 0;
for(int q=0; q<size(); q++) if(f(a[q])) std::swap(a[p++],a[q]);
a.resize(p); return *this;
}
private: Base a;
};
template<class IStr, class U, class T>
IStr& operator>>(IStr& is, vec<std::pair<U,T>>& v){ for(auto& x:v){ is >> x.first >> x.second; } return is; }
template<class IStr, class T>
IStr& operator>>(IStr& is, vec<T>& v){ for(auto& x:v){ is >> x; } return is; }
template<class OStr, class T>
OStr& operator<<(OStr& os, const vec<T>& v){
for(int i=0; i<v.size(); i++){
if(i){ os << ' '; } os << v[i];
} return os;
}
#include <cassert>
namespace nachia{
template<class Elem>
class CsrArray{
public:
struct ListRange{
using iterator = typename std::vector<Elem>::iterator;
iterator begi, endi;
iterator begin() const { return begi; }
iterator end() const { return endi; }
int size() const { return (int)std::distance(begi, endi); }
Elem& operator[](int i) const { return begi[i]; }
};
struct ConstListRange{
using iterator = typename std::vector<Elem>::const_iterator;
iterator begi, endi;
iterator begin() const { return begi; }
iterator end() const { return endi; }
int size() const { return (int)std::distance(begi, endi); }
const Elem& operator[](int i) const { return begi[i]; }
};
private:
int m_n;
std::vector<Elem> m_list;
std::vector<int> m_pos;
public:
CsrArray() : m_n(0), m_list(), m_pos() {}
static CsrArray Construct(int n, std::vector<std::pair<int, Elem>> items){
CsrArray res;
res.m_n = n;
std::vector<int> buf(n+1, 0);
for(auto& [u,v] : items){ ++buf[u]; }
for(int i=1; i<=n; i++) buf[i] += buf[i-1];
res.m_list.resize(buf[n]);
for(int i=(int)items.size()-1; i>=0; i--){
res.m_list[--buf[items[i].first]] = std::move(items[i].second);
}
res.m_pos = std::move(buf);
return res;
}
static CsrArray FromRaw(std::vector<Elem> list, std::vector<int> pos){
CsrArray res;
res.m_n = pos.size() - 1;
res.m_list = std::move(list);
res.m_pos = std::move(pos);
return res;
}
ListRange operator[](int u) { return ListRange{ m_list.begin() + m_pos[u], m_list.begin() + m_pos[u+1] }; }
ConstListRange operator[](int u) const { return ConstListRange{ m_list.begin() + m_pos[u], m_list.begin() + m_pos[u+1] }; }
int size() const { return m_n; }
int fullSize() const { return (int)m_list.size(); }
};
} // namespace nachia
namespace nachia{
struct Graph {
public:
struct Edge{
int from, to;
void reverse(){ std::swap(from, to); }
};
Graph(int n = 0, bool undirected = false, int m = 0) : m_n(n), m_e(m), m_isUndir(undirected) {}
Graph(int n, const std::vector<std::pair<int, int>>& edges, bool undirected = false) : m_n(n), m_isUndir(undirected){
m_e.resize(edges.size());
for(std::size_t i=0; i<edges.size(); i++) m_e[i] = { edges[i].first, edges[i].second };
}
template<class Cin>
static Graph Input(Cin& cin, int n, bool undirected, int m, bool offset = 0){
Graph res(n, undirected, m);
for(int i=0; i<m; i++){
int u, v; cin >> u >> v;
res[i].from = u - offset;
res[i].to = v - offset;
}
return res;
}
int numVertices() const noexcept { return m_n; }
int numEdges() const noexcept { return int(m_e.size()); }
int addNode() noexcept { return m_n++; }
int addEdge(int from, int to){ m_e.push_back({ from, to }); return numEdges() - 1; }
Edge& operator[](int ei) noexcept { return m_e[ei]; }
const Edge& operator[](int ei) const noexcept { return m_e[ei]; }
Edge& at(int ei) { return m_e.at(ei); }
const Edge& at(int ei) const { return m_e.at(ei); }
auto begin(){ return m_e.begin(); }
auto end(){ return m_e.end(); }
auto begin() const { return m_e.begin(); }
auto end() const { return m_e.end(); }
bool isUndirected() const noexcept { return m_isUndir; }
void reverseEdges() noexcept { for(auto& e : m_e) e.reverse(); }
void contract(int newV, const std::vector<int>& mapping){
assert(numVertices() == int(mapping.size()));
for(int i=0; i<numVertices(); i++) assert(0 <= mapping[i] && mapping[i] < newV);
for(auto& e : m_e){ e.from = mapping[e.from]; e.to = mapping[e.to]; }
m_n = newV;
}
std::vector<Graph> induce(int num, const std::vector<int>& mapping) const {
int n = numVertices();
assert(n == int(mapping.size()));
for(int i=0; i<n; i++) assert(-1 <= mapping[i] && mapping[i] < num);
std::vector<int> indexV(n), newV(num);
for(int i=0; i<n; i++) if(mapping[i] >= 0) indexV[i] = newV[mapping[i]]++;
std::vector<Graph> res; res.reserve(num);
for(int i=0; i<num; i++) res.emplace_back(newV[i], isUndirected());
for(auto e : m_e) if(mapping[e.from] == mapping[e.to] && mapping[e.to] >= 0) res[mapping[e.to]].addEdge(indexV[e.from], indexV[e.to]);
return res;
}
CsrArray<int> getEdgeIndexArray(bool undirected) const {
std::vector<std::pair<int, int>> src;
src.reserve(numEdges() * (undirected ? 2 : 1));
for(int i=0; i<numEdges(); i++){
auto e = operator[](i);
src.emplace_back(e.from, i);
if(undirected) src.emplace_back(e.to, i);
}
return CsrArray<int>::Construct(numVertices(), src);
}
CsrArray<int> getEdgeIndexArray() const { return getEdgeIndexArray(isUndirected()); }
CsrArray<int> getAdjacencyArray(bool undirected) const {
std::vector<std::pair<int, int>> src;
src.reserve(numEdges() * (undirected ? 2 : 1));
for(auto e : m_e){
src.emplace_back(e.from, e.to);
if(undirected) src.emplace_back(e.to, e.from);
}
return CsrArray<int>::Construct(numVertices(), src);
}
CsrArray<int> getAdjacencyArray() const { return getAdjacencyArray(isUndirected()); }
private:
int m_n;
std::vector<Edge> m_e;
bool m_isUndir;
};
} // namespace nachia
namespace nachia {
struct Dsu{
private:
int N;
std::vector<int> P;
std::vector<int> H;
public:
Dsu() : N(0) {}
Dsu(int n) : N(n), P(n, -1), H(n) {
for(int i=0; i<n; i++) H[i] = i;
}
int leader(int u){
if(P[u] < 0) return u;
int v = P[u];
while(P[v] >= 0){ P[u] = P[v]; u = v; v = P[v]; }
return P[u];
}
int append(){
int n = P.size();
P.push_back(-1);
H.push_back(n);
return n;
}
int label(int u){ return H[leader(u)]; }
int operator[](int u){ return H[leader(u)]; }
void merge(int u, int v, int newLabel){
if(newLabel < 0) newLabel = u;
u = leader(u);
v = leader(v);
if(u == v){ H[u] = newLabel; return; }
N--;
if(-P[u] < -P[v]) std::swap(u, v);
P[u] += P[v];
H[P[v] = u] = newLabel;
}
int merge(int u, int v){ merge(u, v, u); return u; }
int count(){ return N; }
int size(int u){ return -P[leader(u)]; }
bool same(int u, int v){ return leader(u) == leader(v); }
};
} // namespace nachia
namespace nachia{
struct HeavyLightDecomposition{
private:
int N;
std::vector<int> P;
std::vector<int> PP;
std::vector<int> PD;
std::vector<int> D;
std::vector<int> I;
std::vector<int> rangeL;
std::vector<int> rangeR;
public:
HeavyLightDecomposition(const CsrArray<int>& E = CsrArray<int>::Construct(1, {}), int root = 0){
N = E.size();
P.assign(N, -1);
I = {root};
I.reserve(N);
for(int i=0; i<(int)I.size(); i++){
int p = I[i];
for(int e : E[p]) if(P[p] != e){
I.push_back(e);
P[e] = p;
}
}
std::vector<int> Z(N, 1);
std::vector<int> nx(N, -1);
PP.resize(N);
for(int i=0; i<N; i++) PP[i] = i;
for(int i=N-1; i>=1; i--){
int p = I[i];
Z[P[p]] += Z[p];
if(nx[P[p]] == -1) nx[P[p]] = p;
if(Z[nx[P[p]]] < Z[p]) nx[P[p]] = p;
}
for(int p : I) if(nx[p] != -1) PP[nx[p]] = p;
PD.assign(N,N);
PD[root] = 0;
D.assign(N,0);
for(int p : I) if(p != root){
PP[p] = PP[PP[p]];
PD[p] = std::min(PD[PP[p]], PD[P[p]]+1);
D[p] = D[P[p]]+1;
}
rangeL.assign(N,0);
rangeR.assign(N,0);
for(int p : I){
rangeR[p] = rangeL[p] + Z[p];
int ir = rangeR[p];
for(int e : E[p]) if(P[p] != e) if(e != nx[p]){
rangeL[e] = (ir -= Z[e]);
}
if(nx[p] != -1){
rangeL[nx[p]] = rangeL[p] + 1;
}
}
I.resize(N);
for(int i=0; i<N; i++) I[rangeL[i]] = i;
}
HeavyLightDecomposition(const Graph& tree, int root = 0)
: HeavyLightDecomposition(tree.getAdjacencyArray(true), root) {}
int numVertices() const { return N; }
int depth(int p) const { return D[p]; }
int toSeq(int vtx) const { return rangeL[vtx]; }
int toVtx(int seqidx) const { return I[seqidx]; }
int toSeq2In(int vtx) const { return rangeL[vtx] * 2 - D[vtx]; }
int toSeq2Out(int vtx) const { return rangeR[vtx] * 2 - D[vtx] - 1; }
int parentOf(int v) const { return P[v]; }
int heavyRootOf(int v) const { return PP[v]; }
int heavyChildOf(int v) const {
if(toSeq(v) == N-1) return -1;
int cand = toVtx(toSeq(v) + 1);
if(PP[v] == PP[cand]) return cand;
return -1;
}
int lca(int u, int v) const {
if(PD[u] < PD[v]) std::swap(u, v);
while(PD[u] > PD[v]) u = P[PP[u]];
while(PP[u] != PP[v]){ u = P[PP[u]]; v = P[PP[v]]; }
return (D[u] > D[v]) ? v : u;
}
int dist(int u, int v) const {
return depth(u) + depth(v) - depth(lca(u,v)) * 2;
}
struct Range{
int l; int r;
int size() const { return r-l; }
bool includes(int x) const { return l <= x && x < r; }
};
std::vector<Range> path(int r, int c, bool include_root = true, bool reverse_path = false) const {
if(PD[c] < PD[r]) return {};
std::vector<Range> res(PD[c]-PD[r]+1);
for(int i=0; i<(int)res.size()-1; i++){
res[i] = { rangeL[PP[c]], rangeL[c]+1 };
c = P[PP[c]];
}
if(PP[r] != PP[c] || D[r] > D[c]) return {};
res.back() = { rangeL[r]+(include_root?0:1), rangeL[c]+1 };
if(res.back().l == res.back().r) res.pop_back();
if(!reverse_path) std::reverse(res.begin(),res.end());
else for(auto& a : res) a = { N - a.r, N - a.l };
return res;
}
Range subtree(int p){ return { rangeL[p], rangeR[p] }; }
int median(int x, int y, int z) const {
return lca(x,y) ^ lca(y,z) ^ lca(x,z);
}
int la(int from, int to, int d) const {
if(d < 0) return -1;
int g = lca(from,to);
int dist0 = D[from] - D[g] * 2 + D[to];
if(dist0 < d) return -1;
int p = from;
if(D[from] - D[g] < d){ p = to; d = dist0 - d; }
while(D[p] - D[PP[p]] < d){
d -= D[p] - D[PP[p]] + 1;
p = P[PP[p]];
}
return I[rangeL[p] - d];
}
};
} // namespace nachia
#include <cstdio>
#include <cctype>
#include <cstdint>
namespace nachia{
struct CInStream{
private:
static const unsigned int INPUT_BUF_SIZE = 1 << 17;
unsigned int p = INPUT_BUF_SIZE;
static char Q[INPUT_BUF_SIZE];
public:
using MyType = CInStream;
char seekChar(){
if(p == INPUT_BUF_SIZE){
size_t len = fread(Q, 1, INPUT_BUF_SIZE, stdin);
if(len != INPUT_BUF_SIZE) Q[len] = '\0';
p = 0;
}
return Q[p];
}
void skipSpace(){ while(isspace(seekChar())) p++; }
private:
template<class T, int sp = 1>
T nextUInt(){
if constexpr (sp) skipSpace();
T buf = 0;
while(true){
char tmp = seekChar();
if('9' < tmp || tmp < '0') break;
buf = buf * 10 + (tmp - '0');
p++;
}
return buf;
}
public:
uint32_t nextU32(){ return nextUInt<uint32_t>(); }
int32_t nextI32(){
skipSpace();
if(seekChar() == '-'){
p++; return (int32_t)(-nextUInt<uint32_t, 0>());
}
return (int32_t)nextUInt<uint32_t, 0>();
}
uint64_t nextU64(){ return nextUInt<uint64_t>();}
int64_t nextI64(){
skipSpace();
if(seekChar() == '-'){
p++; return (int64_t)(-nextUInt<int64_t, 0>());
}
return (int64_t)nextUInt<int64_t, 0>();
}
template<class T>
T nextInt(){
skipSpace();
if(seekChar() == '-'){
p++;
return - nextUInt<T, 0>();
}
return nextUInt<T, 0>();
}
char nextChar(){ skipSpace(); char buf = seekChar(); p++; return buf; }
std::string nextToken(){
skipSpace();
std::string buf;
while(true){
char ch = seekChar();
if(isspace(ch) || ch == '\0') break;
buf.push_back(ch);
p++;
}
return buf;
}
MyType& operator>>(unsigned int& dest){ dest = nextU32(); return *this; }
MyType& operator>>(int& dest){ dest = nextI32(); return *this; }
MyType& operator>>(unsigned long& dest){ dest = nextU64(); return *this; }
MyType& operator>>(long& dest){ dest = nextI64(); return *this; }
MyType& operator>>(unsigned long long& dest){ dest = nextU64(); return *this; }
MyType& operator>>(long long& dest){ dest = nextI64(); return *this; }
MyType& operator>>(std::string& dest){ dest = nextToken(); return *this; }
MyType& operator>>(char& dest){ dest = nextChar(); return *this; }
} cin;
struct FastOutputTable{
char LZ[1000][4] = {};
char NLZ[1000][4] = {};
constexpr FastOutputTable(){
using u32 = uint_fast32_t;
for(u32 d=0; d<1000; d++){
LZ[d][0] = ('0' + d / 100 % 10);
LZ[d][1] = ('0' + d / 10 % 10);
LZ[d][2] = ('0' + d / 1 % 10);
LZ[d][3] = '\0';
}
for(u32 d=0; d<1000; d++){
u32 i = 0;
if(d >= 100) NLZ[d][i++] = ('0' + d / 100 % 10);
if(d >= 10) NLZ[d][i++] = ('0' + d / 10 % 10);
if(d >= 1) NLZ[d][i++] = ('0' + d / 1 % 10);
NLZ[d][i++] = '\0';
}
}
};
struct COutStream{
private:
using u32 = uint32_t;
using u64 = uint64_t;
using MyType = COutStream;
static const u32 OUTPUT_BUF_SIZE = 1 << 17;
static char Q[OUTPUT_BUF_SIZE];
static constexpr FastOutputTable TB = FastOutputTable();
u32 p = 0;
static constexpr u32 P10(u32 d){ return d ? P10(d-1)*10 : 1; }
static constexpr u64 P10L(u32 d){ return d ? P10L(d-1)*10 : 1; }
template<class T, class U> static void Fil(T& m, U& l, U x){ m = l/x; l -= m*x; }
void next_dig9(u32 x){
u32 y;
Fil(y, x, P10(6));
nextCstr(TB.LZ[y]);
Fil(y, x, P10(3));
nextCstr(TB.LZ[y]); nextCstr(TB.LZ[x]);
}
public:
void nextChar(char c){
Q[p++] = c;
if(p == OUTPUT_BUF_SIZE){ fwrite(Q, p, 1, stdout); p = 0; }
}
void nextEoln(){ nextChar('\n'); }
void nextCstr(const char* s){ while(*s) nextChar(*(s++)); }
void nextU32(uint32_t x){
u32 y = 0;
if(x >= P10(9)){
Fil(y, x, P10(9));
nextCstr(TB.NLZ[y]); next_dig9(x);
}
else if(x >= P10(6)){
Fil(y, x, P10(6));
nextCstr(TB.NLZ[y]);
Fil(y, x, P10(3));
nextCstr(TB.LZ[y]); nextCstr(TB.LZ[x]);
}
else if(x >= P10(3)){
Fil(y, x, P10(3));
nextCstr(TB.NLZ[y]); nextCstr(TB.LZ[x]);
}
else if(x >= 1) nextCstr(TB.NLZ[x]);
else nextChar('0');
}
void nextI32(int32_t x){
if(x >= 0) nextU32(x);
else{ nextChar('-'); nextU32((u32)-x); }
}
void nextU64(uint64_t x){
u32 y = 0;
if(x >= P10L(18)){
Fil(y, x, P10L(18));
nextU32(y);
Fil(y, x, P10L(9));
next_dig9(y); next_dig9(x);
}
else if(x >= P10L(9)){
Fil(y, x, P10L(9));
nextU32(y); next_dig9(x);
}
else nextU32(x);
}
void nextI64(int64_t x){
if(x >= 0) nextU64(x);
else{ nextChar('-'); nextU64((u64)-x); }
}
template<class T>
void nextInt(T x){
if(x < 0){ nextChar('-'); x = -x; }
if(!(0 < x)){ nextChar('0'); return; }
std::string buf;
while(0 < x){
buf.push_back('0' + (int)(x % 10));
x /= 10;
}
for(int i=(int)buf.size()-1; i>=0; i--){
nextChar(buf[i]);
}
}
void writeToFile(bool flush = false){
fwrite(Q, p, 1, stdout);
if(flush) fflush(stdout);
p = 0;
}
COutStream(){ Q[0] = 0; }
~COutStream(){ writeToFile(); }
MyType& operator<<(unsigned int tg){ nextU32(tg); return *this; }
MyType& operator<<(unsigned long tg){ nextU64(tg); return *this; }
MyType& operator<<(unsigned long long tg){ nextU64(tg); return *this; }
MyType& operator<<(int tg){ nextI32(tg); return *this; }
MyType& operator<<(long tg){ nextI64(tg); return *this; }
MyType& operator<<(long long tg){ nextI64(tg); return *this; }
MyType& operator<<(const std::string& tg){ nextCstr(tg.c_str()); return *this; }
MyType& operator<<(const char* tg){ nextCstr(tg); return *this; }
MyType& operator<<(char tg){ nextChar(tg); return *this; }
} cout;
char CInStream::Q[INPUT_BUF_SIZE];
char COutStream::Q[OUTPUT_BUF_SIZE];
} // namespace nachia
#define rep(i,n) for(int i=0; i<(int)(n); i++)
int main(){
using namespace std;
using Modint = atcoder::static_modint<998244353>;
using nachia::cin;
using nachia::cout;
int N, M; cin >> N >> M;
auto graph = nachia::Graph::Input(cin, N, false, M, 1);
auto mtree = nachia::Graph(N, false);
auto dsu = nachia::Dsu(N);
graph.reverseEdges();
auto adj = graph.getAdjacencyArray();
rep(u,N) for(int v : adj[u]) if(!dsu.same(u, v)){
mtree.addEdge(u, dsu[v]);
dsu.merge(u, v, u);
}
auto hld = nachia::HeavyLightDecomposition(mtree, N-1);
auto ds = atcoder::fenwick_tree<Modint>(N+1);
auto rangeAdd = [&](int l, int r, Modint val){ ds.add(l, val); ds.add(r, -val); };
auto pointGet = [&](int p) -> Modint { return ds.sum(0, p+1); };
Modint ans = 0;
rep(v,N){
sort(adj[v].begin(), adj[v].end(), [&](int a, int b){ return hld.toSeq(a) < hld.toSeq(b); });
Modint f = 1;
for(int u : adj[v]) f += pointGet(hld.toSeq(u));
rep(i,adj[v].size()-1) f -= pointGet(hld.toSeq(hld.lca(adj[v][i], adj[v][i+1])));
auto [l,r] = hld.subtree(v);
rangeAdd(l, r, f);
ans += f;
}
cout << ans.val() << '\n';
return 0;
}