結果
問題 | No.1554 array_and_me |
ユーザー |
![]() |
提出日時 | 2021-06-24 15:35:41 |
言語 | C++17 (gcc 13.3.0 + boost 1.87.0) |
結果 |
AC
|
実行時間 | 84 ms / 2,000 ms |
コード長 | 3,323 bytes |
コンパイル時間 | 2,335 ms |
コンパイル使用メモリ | 208,636 KB |
最終ジャッジ日時 | 2025-01-22 11:47:29 |
ジャッジサーバーID (参考情報) |
judge3 / judge2 |
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ファイルパターン | 結果 |
---|---|
sample | AC * 1 |
other | AC * 41 |
ソースコード
#include<bits/stdc++.h>using namespace std;#define ALL(x) begin(x),end(x)#define rep(i,n) for(int i=0;i<(n);i++)#define debug(v) cout<<#v<<":";for(auto x:v){cout<<x<<' ';}cout<<endl;#define mod 998244353using ll=long long;const int INF=1000000000;const ll LINF=1001002003004005006ll;int dx[]={1,0,-1,0},dy[]={0,1,0,-1};template<class T>bool chmax(T &a,const T &b){if(a<b){a=b;return true;}return false;}template<class T>bool chmin(T &a,const T &b){if(b<a){a=b;return true;}return false;}struct IOSetup{IOSetup(){cin.tie(0);ios::sync_with_stdio(0);cout<<fixed<<setprecision(12);}} iosetup;template<typename T>ostream &operator<<(ostream &os,const vector<T>&v){for(int i=0;i<(int)v.size();i++) os<<v[i]<<(i+1==(int)v.size()?"":" ");return os;}template<typename T>istream &operator>>(istream &is,vector<T>&v){for(T &x:v)is>>x;return is;}template<ll Mod>struct ModInt{long long x;ModInt():x(0){}ModInt(long long y):x(y>=0?y%Mod:(Mod-(-y)%Mod)%Mod){}ModInt &operator+=(const ModInt &p){if((x+=p.x)>=Mod) x-=Mod;return *this;}ModInt &operator-=(const ModInt &p){if((x+=Mod-p.x)>=Mod)x-=Mod;return *this;}ModInt &operator*=(const ModInt &p){x=(int)(1ll*x*p.x%Mod);return *this;}ModInt &operator/=(const ModInt &p){(*this)*=p.inverse();return *this;}ModInt operator-()const{return ModInt(-x);}ModInt operator+(const ModInt &p)const{return ModInt(*this)+=p;}ModInt operator-(const ModInt &p)const{return ModInt(*this)-=p;}ModInt operator*(const ModInt &p)const{return ModInt(*this)*=p;}ModInt operator/(const ModInt &p)const{return ModInt(*this)/=p;}bool operator==(const ModInt &p)const{return x==p.x;}bool operator!=(const ModInt &p)const{return x!=p.x;}ModInt inverse()const{int a=x,b=Mod,u=1,v=0,t;while(b>0){t=a/b;swap(a-=t*b,b);swap(u-=t*v,v);}return ModInt(u);}ModInt pow(long long n)const{ModInt ret(1),mul(x);while(n>0){if(n&1) ret*=mul;mul*=mul;n>>=1;}return ret;}friend ostream &operator<<(ostream &os,const ModInt &p){return os<<p.x;}friend istream &operator>>(istream &is,ModInt &a){long long t;is>>t;a=ModInt<Mod>(t);return (is);}static int get_mod(){return Mod;}};using mint=ModInt<998244353>;vector<mint> fac(1,1);void solve(){int N,K;cin>>N>>K;vector<int> A(N);cin>>A;mint S=0;for(auto &x:A) S+=x;S=S.inverse();vector<mint> p(N);rep(i,N) p[i]=S*A[i];using P=pair<int,int>;priority_queue<P,vector<P>,function<bool(P,P)>> que([&](P l,P r){return A[l.first]*(r.second+1)<A[r.first]*(l.second+1);});rep(i,N) que.emplace(i,0);rep(_,K){auto [idx, t]=que.top();que.pop();que.emplace(idx, t+1);}mint res=fac[K];while(!que.empty()){auto [idx, t]=que.top();que.pop();res*=mint(p[idx]).pow(t);res*=fac[t].inverse();}cout<<res<<endl;}signed main(){for(int i=1;i<=500000;i++) fac.push_back(fac.back()*i);int q;cin>>q;while(q--) solve();return 0;}