結果
| 問題 | No.1989 Pairing Multiset |
| ユーザー |
 unti
|
| 提出日時 | 2022-07-19 02:44:06 |
| 言語 | C++17 (gcc 13.3.0 + boost 1.87.0) |
| 結果 |
AC
|
| 実行時間 | 585 ms / 2,000 ms |
| コード長 | 6,256 bytes |
| コンパイル時間 | 2,959 ms |
| コンパイル使用メモリ | 222,732 KB |
| 最終ジャッジ日時 | 2025-01-30 11:02:31 |
|
ジャッジサーバーID （参考情報） |
judge4 / judge3 |
（要ログイン）
| ファイルパターン | 結果 |
|---|---|
| sample | AC * 3 |
| other | AC * 18 |
ソースコード
#pragma GCC optimize("Ofast")#include <bits/stdc++.h>using namespace std;using ll = long long int ;using ld = long double ;using P = pair<ll,ll>;using Graph= vector<vector<ll>>;struct edge{ll to ; ll cost ;} ;using graph =vector<vector<edge>> ;#define rep(i,n) for (ll i=0; i < (n); ++i)#define rep2(i,n,m) for(ll i=n;i<=m;i++)#define rep3(i,n,m) for(ll i=n;i>=m;i--)#define pb push_back#define eb emplace_back#define ppb pop_back#define mpa make_pair#define fi first#define se second#define set20 cout<<fixed<<setprecision(20) ;const ll INF=1e18 ;inline void chmax(ll& a,ll b){a=max(a,b);}inline void chmin(ll& a,ll b){a=min(a,b);}long double pi=acos(-1) ;ll gcd(ll a, ll b) { return b?gcd(b,a%b):a;}ll lcm(ll a, ll b) { return a/gcd(a,b)*b;}ll dx[4] {1,0,-1,0} ;ll dy[4] {0,1,0,-1} ;#define debug cout<<888<<endl ;// ミント//int mod ; //任意modではconst外すconst int mod =//1e9+7 ;//924844033;998244353;struct mint {ll x; // typedef long long ll;mint(ll x=0):x((x%mod+mod)%mod){}mint operator-() const { return mint(-x);}mint& operator+=(const mint a) {if ((x += a.x) >= mod) x -= mod;return *this;}mint& operator-=(const mint a) {if ((x += mod-a.x) >= mod) x -= mod;return *this;}mint& operator*=(const mint a) { (x *= a.x) %= mod; return *this;}mint operator+(const mint a) const { return mint(*this) += a;}mint operator-(const mint a) const { return mint(*this) -= a;}mint operator*(const mint a) const { return mint(*this) *= a;}mint pow(ll t) const {if (!t) return 1;mint a = pow(t>>1);a *= a;if (t&1) a *= *this;return a;}// for prime modmint inv() const { return pow(mod-2);}mint& operator/=(const mint a) { return *this *= a.inv();}mint operator/(const mint a) const { return mint(*this) /= a;}};istream& operator>>(istream& is, const mint& a) { return is >> a.x;}ostream& operator<<(ostream& os, const mint& a) { return os << a.x;}//昆布struct combination {vector<mint> fact, ifact;combination(int n):fact(n+1),ifact(n+1) {assert(n < mod); //任意modではここ消すcombmain内にfact[0] = 1;for (int i = 1; i <= n; ++i) fact[i] = fact[i-1]*i;ifact[n] = fact[n].inv();for (int i = n; i >= 1; --i) ifact[i-1] = ifact[i]*i;}mint operator()(int n, int k) {if (k < 0 || k > n) return 0;return fact[n]*ifact[k]*ifact[n-k];}mint p(int n,int k){return fact[n]*ifact[n-k] ; //kは個数}} c(1000005);mint modpow(ll a,ll b){if(b==0) return 1 ;mint c= modpow(a,b/2) ;if(b%2==1) return c*c*a ;else return c*c ;}mint mmodpow(mint a,ll b){if(b==0) return 1ll ;mint c=mmodpow(a,(b/2)) ;if(b%2==1) return c*c*a ;else return c*c ;}mint komb(ll n,ll m){mint x=1 ;mint y=1 ;rep(i,m){x*= n-i ;y*= i+1 ;}return x/y ;}map<ll,ll> factor(ll n){ //素因数とオーダーをマップで管理map <ll,ll> ord ;for(ll i=2;i*i<=n;i++){if(n%i==0){int res=0;while(n%i==0){n/=i;res++;}ord[i]=res;}}if(n!=1) ord[n]++;return ord ;}struct UnionFind {vector<int> d;UnionFind(int n=0): d(n,-1) {}int find(int x) {if (d[x] < 0) return x;return d[x] = find(d[x]);}bool unite(int x, int y) {x = find(x); y = find(y);if (x == y) return false;if (d[x] > d[y]) swap(x,y);d[x] += d[y];d[y] = x;return true;}bool same(int x, int y) { return find(x) == find(y);}int size(int x) { return -d[find(x)];}};// sum(x) x以下の和// sum(a,b) a以上b以下の和template<typename T>struct BIT {int n;vector<T> d;BIT(int n=0):n(n),d(n+1) {}void add(int i, T x=1) { //x=1ならsumは個数のカウントfor (i++; i <= n; i += i&-i) {d[i] += x;}}T sum(int i) {T x = 0;for (i++; i; i -= i&-i) {x += d[i];}return x;}T sum(int i,int j) {if(i>0) return sum(j)-sum(i-1);else return sum(j); }};template< typename flow_t >struct Dinic {const flow_t INF;struct edge {int to;flow_t cap;int rev;bool isrev;int idx;};vector< vector< edge > > graph;vector< int > min_cost, iter;Dinic(int V) : INF(numeric_limits< flow_t >::max()), graph(V) {}void add_edge(int from, int to, flow_t cap, int idx = -1) {graph[from].emplace_back((edge) {to, cap, (int) graph[to].size(), false, idx});graph[to].emplace_back((edge) {from, 0, (int) graph[from].size() - 1, true, idx});}bool bfs(int s, int t) {min_cost.assign(graph.size(), -1);queue< int > que;min_cost[s] = 0;que.push(s);while(!que.empty() && min_cost[t] == -1) {int p = que.front();que.pop();for(auto &e : graph[p]) {if(e.cap > 0 && min_cost[e.to] == -1) {min_cost[e.to] = min_cost[p] + 1;que.push(e.to);}}}return min_cost[t] != -1;}flow_t dfs(int idx, const int t, flow_t flow) {if(idx == t) return flow;for(int &i = iter[idx]; i < graph[idx].size(); i++) {edge &e = graph[idx][i];if(e.cap > 0 && min_cost[idx] < min_cost[e.to]) {flow_t d = dfs(e.to, t, min(flow, e.cap));if(d > 0) {e.cap -= d;graph[e.to][e.rev].cap += d;return d;}}}return 0;}flow_t max_flow(int s, int t) {flow_t flow = 0;while(bfs(s, t)) {iter.assign(graph.size(), 0);flow_t f = 0;while((f = dfs(s, t, INF)) > 0) flow += f;}return flow;}void output() {for(int i = 0; i < graph.size(); i++) {for(auto &e : graph[i]) {if(e.isrev) continue;auto &rev_e = graph[e.to][e.rev];cout << i << "->" << e.to << " (flow: " << rev_e.cap << "/" << e.cap + rev_e.cap << ")" << endl;}}}};int main(){ios::sync_with_stdio(false) ;cin.tie(nullptr) ;ll n,m; cin>>n>>m;mint ans=mint(n*m)/mint(2*n+1);//ans*=c(2*n+m,2*n);rep(i,2*n){ans*=mint(2*n+m-i)/mint(i+1);}cout<<ans<<endl;return 0;}