Init

2023-12-23 22:23:48 +08:00
commit 43ced8bd2a
58 changed files with 5702 additions and 0 deletions
--- a/ACMOJ-1018.cpp
+++ b/ACMOJ-1018.cpp
@ -0,0 +1,136 @@
+#include<iostream>
+#include<cstring>
+#include<algorithm>
+#include<cassert>
+#include<vector>
+#include<random>
+// #include<map>
+using namespace std;
+typedef long long LL;
+typedef pair<int,LL> SufType;
+const int maxn=1005;
+int N,K,a[maxn];
+bool used[maxn];
+vector<int> position,number;
+LL OuterPair[20][20],stk[20],Answer,TotalNotFixed,InnerPair[1<<14][20];
+int hsh[(1<<14)+1];
+int PreLength,SufLength;
+struct Hash_SufType2LongLong
+{
+	const static int PoolSize=17297280*3;
+	const static LL a=233331,b=19260817;
+	LL Pool[PoolSize];
+	int head[PoolSize],nxt[PoolSize],stv[PoolSize],CntV[PoolSize],PoolCnt=0;
+	inline LL& operator[](const SufType &key)
+	{
+		const LL HashValue=(key.first*a+key.second+b)%PoolSize;
+		// return Pool[HashValue];
+		int p=head[HashValue];
+		while(p)
+		{
+			if(stv[p]==key.first&&CntV[p]==key.second) return Pool[p];
+			p=nxt[p];
+		}
+		PoolCnt++;
+		nxt[PoolCnt]=head[HashValue];
+		stv[PoolCnt]=key.first;
+		CntV[PoolCnt]=key.second;
+		head[HashValue]=PoolCnt;
+		return Pool[PoolCnt];
+	}
+}SufData;
+void dfs(int dep,LL CurrentPair,int st)
+{
+	if(dep==PreLength)
+	{
+		Answer+=SufData[SufType(((1<<TotalNotFixed)-1)^st,K-CurrentPair)];
+		return;
+	}
+	int valid=((1<<TotalNotFixed)-1)^st;
+	for(;valid;valid-=valid&(-valid))
+	{
+		int i=hsh[valid&(-valid)];
+		if((st&(1<<i))==0
+			&&CurrentPair+InnerPair[st][i]+OuterPair[dep][i]<=K
+			&&!(K>CurrentPair+(TotalNotFixed-dep)*(TotalNotFixed-dep-1)/2+(TotalNotFixed-dep)*(N-TotalNotFixed+dep)))
+		{
+			stk[dep]=number[i];
+			dfs(dep+1,CurrentPair+InnerPair[st][i]+OuterPair[dep][i],st|(1<<i));
+		}
+	}
+}
+int main()
+{
+#ifdef local
+	freopen("pro.in","r",stdin);
+#endif
+	scanf("%d%d",&N,&K);
+	for(int i=1;i<=N;i++)
+	{
+		scanf("%d",&a[i]);
+		used[a[i]]=true;
+		if(a[i]==0) position.push_back(i);
+		assert(0<=a[i]&&a[i]<=N);
+	}
+	LL AlreadyHave=0;
+	for(int i=1;i<=N;i++)
+		for(int j=i+1;j<=N;j++)
+			if(a[i]!=0&&a[j]!=0&&a[i]>a[j])
+				AlreadyHave++;
+	for(int i=1;i<=N;i++)
+		if(!used[i])
+			number.push_back(i);
+	TotalNotFixed=position.size();
+	for(int i=0;i<TotalNotFixed;i++)
+	{
+		const int pos=position[i];
+		for(int j=0;j<TotalNotFixed;j++)
+		{
+			const int num=number[j];
+			for(int k=1;k<=N;k++)
+				if((a[k]!=0&&k<pos&&a[k]>num)||(a[k]!=0&&k>pos&&a[k]<num))
+					OuterPair[i][j]++;
+		}
+	}
+	for(int st=0;st<(1<<TotalNotFixed);st++)
+		for(int p=0;p<TotalNotFixed;p++)
+			for(int i=0;i<TotalNotFixed;i++)
+				if((st&(1<<i))&&number[i]>number[p])
+					InnerPair[st][p]++;
+	if(K>AlreadyHave+TotalNotFixed*(TotalNotFixed-1)/2+TotalNotFixed*(N-TotalNotFixed))
+	{
+		puts("0");
+		return 0;
+	}
+	for(int i=0;i<TotalNotFixed;i++) hsh[1<<i]=i;
+	SufLength=(TotalNotFixed+1)/2;
+	PreLength=TotalNotFixed-SufLength;
+	const int FullStatus=(1<<TotalNotFixed)-1;
+	for(int st=0;st<(1<<TotalNotFixed);st++)
+	{
+		if(__builtin_popcount(st)==SufLength)
+		{
+			const int PreStatus=FullStatus^st;
+			int p[10],pcnt=0;
+			for(int i=0;i<TotalNotFixed;i++)
+				if(st&(1<<i))
+					p[pcnt++]=i;
+			assert(pcnt==SufLength);
+			do
+			{
+				LL tmp=0,AlreadyProced=0;
+				for(int i=0;i<SufLength;i++)
+				{
+					tmp+=OuterPair[TotalNotFixed-SufLength+i][p[i]];
+					tmp+=InnerPair[PreStatus][p[i]];
+					tmp+=InnerPair[AlreadyProced][p[i]];
+					AlreadyProced|=1<<p[i];
+				}
+				SufData[SufType(st,tmp)]++;
+			} while (next_permutation(p,p+SufLength));
+		}
+	}
+	dfs(0,AlreadyHave,0);
+	printf("%lld\n",Answer);
+	return 0;
+}