結果
問題 | No.1300 Sum of Inversions |
ユーザー | yamake |
提出日時 | 2020-11-27 22:48:41 |
言語 | C++14 (gcc 13.3.0 + boost 1.87.0) |
結果 |
AC
|
実行時間 | 825 ms / 2,000 ms |
コード長 | 2,549 bytes |
コンパイル時間 | 1,257 ms |
コンパイル使用メモリ | 100,868 KB |
実行使用メモリ | 34,776 KB |
最終ジャッジ日時 | 2024-07-26 19:08:05 |
合計ジャッジ時間 | 21,566 ms |
ジャッジサーバーID (参考情報) |
judge4 / judge2 |
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ファイルパターン | 結果 |
---|---|
sample | AC * 3 |
other | AC * 34 |
ソースコード
#include<iostream>#include<vector>#include<algorithm>#include<string>#include<queue>#include<cstdio>#include<cmath>#include<map>using namespace std;#define int long long#define rep(i,n) for(int i=0;i<n;++i)#define rep1(i,n) for(int i=1;i<=n;++i)#define ALL(x) x.begin(),x.end()#define debug(output) cout<<#output<<"= "<<output<<endlusing lint=long long;int MOD=998244353;void press(vector<int>& x){map<int,int> memo;int n=x.size();rep(i,n){memo[x[i]]+=1;}int cur=0;for(auto& val:memo){val.second=cur;++cur;}rep(i,n){x[i]=memo[x[i]];}}class SegTree{private:int e=0;int n;vector<int> node;public:int process(int left,int right){if(left==e)return right;if(right==e)return left;return (left+right)%MOD;}SegTree(vector<int> v){int num=1;int size=v.size();while(num<size){num*=2;}n=num;node.resize(2*num-1,e);for(int i=0;i<size;i++)node[i+num-1]=v[i];for(int i=n-2;i>=0;i--)node[i]=process(node[i*2+1],node[i*2+2]);}void update(int x,int val){x+=(n-1);node[x]+=val;node[x]%=MOD;while(x>0){x=(x-1)/2;node[x]=process(node[x*2+1],node[x*2+2]);}}int out(int a,int b,int k=0,int l=0,int r=-1){if(r<0)r=n;if(a>=r||b<=l)return e;if(a<=l&&b>=r)return node[k];int vl=out(a,b,k*2+1,l,(l+r)/2);int vr=out(a,b,k*2+2,(l+r)/2,r);return process(vl,vr);}};signed main(){int n;cin>>n;vector<int> a(n);rep(i,n)cin>>a[i];vector<lint> l(n+1,0),r(n+1,0);vector<lint> lsm(n+1,0),rsm(n+1,0);vector<lint> p=a;press(p);SegTree tree(vector<int>(n+5,0)),treeSm(vector<int>(n+5,0)),hoge(vector<int>(n+5,0));rep(i,n){l[i]=tree.out(p[i]+1,n+2);lsm[i]=treeSm.out(p[i]+1,n+2);tree.update(p[i],1);treeSm.update(p[i],a[i]);}tree=hoge;treeSm=hoge;for(int i=n-1;i>=0;--i){r[i]=tree.out(0,p[i]);rsm[i]=treeSm.out(0,p[i]);tree.update(p[i],1);treeSm.update(p[i],a[i]);}lint res=0;rep1(i,n-2){//debug(i);//printf("%lld %lld %lld %lld\n",l[i],lsm[i],r[i],rsm[i]);res+=(a[i]*l[i]%MOD)*r[i]%MOD;res+=l[i]*rsm[i]%MOD;res+=r[i]*lsm[i]%MOD;res%=MOD;}cout<<res<<"\n";return 0;}