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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#216937#7177. Many Many CyclesExplodingKonjacRE 0ms3864kbC++205.8kb2023-10-16 09:21:502023-10-16 09:21:50

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你现在查看的是最新测评结果

  • [2023-10-16 09:21:50]
  • 评测
  • 测评结果:RE
  • 用时:0ms
  • 内存:3864kb
  • [2023-10-16 09:21:50]
  • 提交

answer

#include <bits/stdc++.h>
using namespace std;
#define OPENIOBUF

namespace FastIO
{

class FastIOBase
{
 protected:
#ifdef OPENIOBUF
	static const int BUFSIZE=1<<16;
	char buf[BUFSIZE+1];
	int buf_p=0;
#endif
	FILE *target;
	FastIOBase(FILE *f): target(f){}
	~FastIOBase()=default;
 public:
#ifdef OPENIOBUF
	virtual void flush()=0;
#endif
};

class FastOutput final: public FastIOBase
{
 private:
	void __putc(char x)
	{
#ifdef OPENIOBUF
		if(buf[buf_p++]=x,buf_p==BUFSIZE) flush();
#else
		putc(x,target);
#endif
	}
	template<typename T>
	void __write(T x)
	{
		char stk[numeric_limits<T>::digits10+1],*top=stk;
		if(x<0) return __putc('-'),__write(-x);
		do *(top++)=x%10,x/=10; while(x);
		for(;top!=stk;__putc(*(--top)+'0'));
	}
 public:
	FastOutput(FILE *f=stdout): FastIOBase(f) {}
#ifdef OPENIOBUF
	~FastOutput() { flush(); }
	void flush() { fwrite(buf,1,buf_p,target),buf_p=0; }
#endif
	FastOutput &operator <<(char x)
	{ return __putc(x),*this; }
	FastOutput &operator <<(const char *s)
	{ for(;*s;__putc(*(s++)));return *this; }
	FastOutput &operator <<(const std::string &s)
	{ return (*this)<<s.c_str(); }
	template<typename T>
	std::enable_if_t<std::is_integral<T>::value,FastOutput&> operator <<(const T &x)
	{ return __write(x),*this; }
	template<typename ...T>
	void writesp(const T &...x)
	{ std::initializer_list<int>{(this->operator<<(x),__putc(' '),0)...}; }
	template<typename ...T>
	void writeln(const T &...x)
	{ std::initializer_list<int>{(this->operator<<(x),__putc('\n'),0)...}; }
	template<typename Iter>
	void writesp(Iter begin,Iter end)
	{ while(begin!=end) (*this)<<*(begin++)<<' '; }
	template<typename Iter>
	void writeln(Iter begin,Iter end)
	{ while(begin!=end) (*this)<<*(begin++)<<'\n'; }
}qout;

class FastInput final: public FastIOBase
{
 private:
	bool __eof;
 public:
	FastInput(FILE *f=stdin): FastIOBase(f),__eof(false)
#ifdef OPENIOBUF
	{ buf_p=BUFSIZE; }
	void flush() { buf[fread(buf,1,BUFSIZE,target)]=EOF,buf_p=0; }
	bool eof()const { return buf[buf_p]==EOF; }
#else
	{}
	bool eof()const { return feof(target); }
#endif
	char get()
	{
		if(__eof) return EOF;
#ifdef OPENIOBUF
		if(buf_p==BUFSIZE) flush();
		char ch=buf[buf_p++];
#else
		char ch=getc(target);
#endif
		return ~ch?ch:(__eof=true,EOF);
	}
	void unget(char c)
	{
		__eof=false;
#ifdef OPENIOBUF
		buf[--buf_p]=c;
#else
		ungetc(c,target);
#endif
	}
	explicit operator bool()const { return !__eof; }
	FastInput &operator >>(char &x)
	{ while(isspace(x=get()));return *this; }
	template<typename T>
	std::enable_if_t<std::is_integral<T>::value,FastInput&> operator >>(T &x)
	{
		char ch,sym=0;x=0;
		while(isspace(ch=get()));
		if(__eof) return *this;
		if(ch=='-') sym=1,ch=get();
		for(;isdigit(ch);x=(x<<1)+(x<<3)+(ch^48),ch=get());
		return unget(ch),sym?x=-x:x,*this;
	}
	FastInput &operator >>(char *s)
	{
		while(isspace(*s=get()));
		if(__eof) return *this;
		for(;!isspace(*s) && !__eof;*(++s)=get());
		return unget(*s),*s='\0',*this;
	}
	FastInput &operator >>(std::string &s)
	{
		char str_buf[(1<<8)+1]={0},*p=str_buf;
		char *const buf_end=str_buf+(1<<8);
		while(isspace(*p=get()));
		if(__eof) return *this;
		for(s.clear(),p++;;p=str_buf)
		{
			for(;p!=buf_end && !isspace(*p=get()) && !__eof;p++);
			if(p!=buf_end) break;
			s.append(str_buf);
		}
		unget(*p),*p='\0',s.append(str_buf);
		return *this;
	}
	template<typename ...T>
	void read(T &...x)
	{ std::initializer_list<int>{(this->operator>>(x),0)...}; }
	template<typename Iter>
	void read(Iter begin,Iter end)
	{ while(begin!=end) (*this)>>*(begin++); }
}qin;

} // namespace FastIO
using FastIO::qin,FastIO::qout;

using LL=long long;
using LD=long double;
using UI=unsigned int;
using ULL=unsigned long long;

#ifndef DADALZY
#define FILEIO(file) freopen(file".in","r",stdin),freopen(file".out","w",stdout)
#define LOG(...) void()
#else
#define FILEIO(file)
#define LOG(...) fprintf(stderr,__VA_ARGS__)
#endif

int n,m;
vector<pair<int,int>> G[5005];

vector<tuple<int,int,int>> E;
int fa[5005];
inline int findFa(int x)
{ return fa[x]!=x?fa[x]=findFa(fa[x]):x; }
inline void merge(int x,int y)
{ fa[findFa(y)]=findFa(x); }

int tot,eul[10005],pos[5005],f[20][10005];
LL dep[5005];
void dfs(int u,int fa=0)
{
	eul[pos[u]=++tot]=u;
	for(auto &[v,w]: G[u])
	{
		if(v==fa) continue;
		dep[v]=dep[u]+w;
		dfs(v,u),eul[++tot]=u;
	}
}
void buildST()
{
	auto cmp=[](int x,int y) { return dep[x]<dep[y]; };
	for(int i=1;i<=tot;i++) f[0][i]=eul[i];
	for(int i=1;(1<<i)<=tot;i++)
		for(int j=1;j+(1<<i)-1<=tot;j++)
			f[i][j]=min(f[i-1][j],f[i-1][j+(1<<(i-1))],cmp);
}
inline int lca(int u,int v)
{
	tie(u,v)=minmax(pos[u],pos[v]);
	int s=__lg(v-u+1),x=f[u][s],y=f[v-(1<<s)+1][s];
	return dep[x]<dep[y]?x:y;
}
inline LL dist(int u,int v)
{
	int w=lca(u,v);
	return dep[u]+dep[v]-2*dep[w];
}

int main()
{
	qin>>n>>m;
	iota(fa+1,fa+n+1,1);
	for(int i=1,u,v,w;i<=m;i++)
	{
		qin>>u>>v>>w;
		if(findFa(u)==findFa(v))
			E.emplace_back(u,v,w);
		else
		{
			merge(u,v);
			G[u].emplace_back(v,w);
			G[v].emplace_back(u,w);
		}
	}
	for(int i=1;i<=n;i++)
	{
		if(findFa(i)!=i) continue;
		G[0].emplace_back(i,0);
	}
	dfs(0),buildST();
	LL ans=0;
	for(auto &[u,v,w]: E)
	{
		if(pos[u]>pos[v]) swap(pos[u],pos[v]);
		LL len=dist(u,v)+w;
		ans=gcd(ans,len);
	}
	for(auto &[u1,v1,w1]: E)
	{
		int z1=lca(u1,v1);
		LL len1=dist(u1,v1);
		for(auto &[u2,v2,w2]: E)
		{
			if(u1==u2 && v1==v2) continue;
			int z2=lca(u2,v2);
			if(dep[z1]>dep[z2] || dist(u1,z2)+dist(z2,v1)!=len1) continue;
			LL len2=dist(u2,v2);
			int k1=lca(u1,u2),k2=lca(v1,v2);
			if(dep[k1]<dep[z2]) k1=z2;
			if(dep[k2]<dep[z2]) k2=z2;
			LL len=len1+len2-dist(k1,k2)+w1+w2;
			ans=gcd(ans,len);
		}
	}
	qout<<ans<<'\n';
	return 0;
}

Details

Tip: Click on the bar to expand more detailed information

Test #1:

score: 100
Accepted
time: 0ms
memory: 3864kb

input:

4 4
1 2 1
2 3 1
3 4 1
4 1 1

output:

4

result:

ok answer is '4'

Test #2:

score: 0
Accepted
time: 0ms
memory: 3816kb

input:

4 5
1 2 1
1 3 2
1 4 1
2 3 1
3 4 1

output:

4

result:

ok answer is '4'

Test #3:

score: -100
Runtime Error

input:

20 50
1 2 8
1 3 1
3 4 5
3 5 9
3 6 5
6 7 6
7 8 8
2 9 2
8 10 3
8 11 7
8 12 5
3 13 4
7 14 3
6 15 7
9 16 6
8 17 7
16 18 9
16 19 3
18 20 10
11 3 2
17 1 1
16 2 2
15 1 1
10 3 2
9 1 2
19 2 1
6 1 2
7 3 1
17 3 2
15 3 2
8 6 2
5 1 2
8 1 2
12 1 1
12 7 1
4 1 2
18 2 1
11 7 1
14 1 1
18 1 1
18 9 1
10 6 1
14 3 2
20 2...

output:


result: