Submission #476312

#	Time	Username	Problem	Language	Result	Execution time	Memory
476312		MonkeyKing	Papričice (COCI20_papricice)	C++14	110 / 110	244 ms	20264 KiB

papricice

//Original Code:
//#include <self/utility>
//#include <self/debug>
//using namespace std;
//int n;
//vector<int> edges[200005];
//int sz[200005];
//int block[200005];
//vector<int> v1,v2;
//
//void calc(int x,int par,vector<int> &v)
//{
//	v.push_back(sz[x]);
//	for(auto u:edges[x])
//	{
//		if(u==par) continue;
//		calc(u,x,v);
//	}
//}
//
//pii go(int x,int par)
//{
//	pii o=mp(n-sz[x],x);
//	pii res=mp(inf,-1);
//	for(auto u:edges[x])
//	{
//		if(u==par) continue;
//		chmax(o.first,sz[u]);
//		chmin(res,go(u,x));
//	}
//	chmin(res,o);
//	return res;
//}
//
//void dfs(int x,int par)
//{
//	sz[x]=1;
//	for(auto u:edges[x])
//	{
//		if(u==par) continue;
//		dfs(u,x);
//		sz[x]+=sz[u];
//	}
//}
//
//int calc(int a,int b,int c)
//{
//	return max({a,b,c})-min({a,b,c});
//}
//
//int calc(const vector<int> &v1,const vector<int> &v2)
//{
//	int res=inf;
//	for(int x:v1)
//	{
//		int m=n-x;
//		int it=lower_bound(all(v2),m/2)-v2.begin();
//		for(int i=max(it-5,0);i<min(it+5,(int)v2.size());i++)
//		{
//			chmin(res,calc(x,v2[i],m-v2[i]));
//		}
//	}
//	return res;
//}
//
//vector<vector<int> > vv;
//int main()
//{
//	freopen("input.txt","r",stdin);
//	cin>>n;
//	for(int i=0;i<n-1;i++)
//	{
//		int x,y;
//		scanf("%d%d",&x,&y);
//		x--;
//		y--;
//		edges[x].emplace_back(y);
//		edges[y].emplace_back(x);
//	}
//	dfs(0,-1);
//	int rt=go(0,-1).second;
//	dfs(rt,-1);
//	sort(all(edges[rt]),[](int x,int y){return sz[x]>sz[y];});
//	for(auto u:edges[rt])
//	{
//		vector<int> t;
//		calc(u,rt,t);
//		sort(all(t));
//		vv.emplace_back(t);
//	}
//	int res=inf;
//	chmin(res,calc(vv[0],vv[1]));
//	int m=n-sz[edges[rt][0]];
//	for(auto x:vv[0])
//	{
//		if(x==sz[edges[rt][0]]) continue;
//		chmin(res,calc(m,x,m-x));
//	}
//	cout<<res<<endl;
//	return 0;
//}

//substituted with C++ Inliner
#ifndef _SELF_UTILITY
#define _SELF_UTILITY 1
#include <numeric>
#include <iostream>
#include <algorithm>
#include <cmath>
#include <stdio.h>
#include <stdlib.h>
#include <vector>
#include <map>
#include <queue>
#include <set>
#include <string>
#include <string.h>
#include <stack>
#include <assert.h>
#include <bitset>
#include <time.h>
#define Endl endl
#define mp make_pair
#define mt make_tuple
#define ll long long 
#define ull unsigned long long
#define pii pair<int,int>
#define over(A) {cout<<A<<endl;exit(0);}
#define all(A) A.begin(),A.end()
#define quickcin ios_base::sync_with_stdio(false);
#ifdef __TAKE_MOD
int mod;
#else
#ifdef __TAKE_CONST_MOD
const int mod=__TAKE_CONST_MOD;
#else
const int mod=1000000007;
#endif
#endif
const int gmod=3;
const int inf=1039074182;
#ifdef __TAKE_CONST_EPS
const double eps=__TAKE_CONST_EPS;
#else
const double eps=1e-9;
#endif
const double pi=3.141592653589793238462643383279;
const ll llinf=2LL*inf*inf;
template <typename T1,typename T2> inline void chmin(T1 &x,T2 b) {if(b<x) x=b;}
template <typename T1,typename T2> inline void chmax(T1 &x,T2 b) {if(b>x) x=b;}
inline void chadd(int &x,int b) {x+=b-mod;x+=(x>>31 & mod);}
template <typename T1,typename T2> inline void chadd(T1 &x,T2 b) {x+=b;if(x>=mod) x-=mod;}
template <typename T1,typename T2> inline void chmul(T1 &x,T2 b) {x=1LL*x*b%mod;}
template <typename T1,typename T2> inline void chmod(T1 &x,T2 b) {x%=b,x+=b;if(x>=b) x-=b;}
template <typename T> inline T mabs(T x) {return (x<0?-x:x);}
using namespace std;
#endif
#ifndef _SELF_DEBUG
#define _SELF_DEBUG 1
#ifndef _SELF_OPERATOR
#define _SELF_OPERATOR 1
using namespace std;
template <typename T>
ostream & operator<<(ostream &cout, const vector<T> &vec)
{
	cout << "{";
	for (int i = 0; i < (int)vec.size(); i++)
	{
		cout << vec[i];
		if (i != (int)vec.size() - 1)
			cout << ',';
	}
	cout << "}";
	return cout;
}

template <typename T1, typename T2>
ostream &operator<<(ostream &cout, pair<T1, T2> p)
{
	cout << "(" << p.first << ',' << p.second << ")";
	return cout;
}

template <typename T, typename T2>
ostream &operator<<(ostream &cout, set<T, T2> s)
{
	vector<T> t;
	for (auto x : s)
		t.push_back(x);
	cout << t;
	return cout;
}

template <typename T, typename T2>
ostream &operator<<(ostream &cout, multiset<T, T2> s)
{
	vector<T> t;
	for (auto x : s)
		t.push_back(x);
	cout << t;
	return cout;
}

template <typename T>
ostream &operator<<(ostream &cout, queue<T> q)
{
	vector<T> t;
	while (q.size())
	{
		t.push_back(q.front());
		q.pop();
	}
	cout << t;
	return cout;
}

template <typename T1, typename T2, typename T3>
ostream &operator<<(ostream &cout, map<T1, T2, T3> m)
{
	for (auto &x : m)
	{
		cout << "Key: " << x.first << ' ' << "Value: " << x.second << endl;
	}
	return cout;
}

template <typename T1, typename T2>
void operator+=(pair<T1, T2> &x,const pair<T1, T2> y)
{
	x.first += y.first;
	x.second += y.second;
}
template <typename T1,typename T2>
pair<T1,T2> operator + (const pair<T1,T2> &x,const pair<T1,T2> &y)
{
	return make_pair(x.first+y.first,x.second+y.second);
}

template <typename T1,typename T2>
pair<T1,T2> operator - (const pair<T1,T2> &x,const pair<T1,T2> &y)
{
	return mp(x.first-y.first,x.second-y.second);
}

template <typename T1, typename T2>
pair<T1, T2> operator-(pair<T1, T2> x)
{
	return make_pair(-x.first, -x.second);
}

template <typename T>
vector<vector<T>> operator~(vector<vector<T>> vec)
{
	vector<vector<T>> v;
	int n = vec.size(), m = vec[0].size();
	v.resize(m);
	for (int i = 0; i < m; i++)
	{
		v[i].resize(n);
	}
	for (int i = 0; i < m; i++)
	{
		for (int j = 0; j < n; j++)
		{
			v[i][j] = vec[j][i];
		}
	}
	return v;
}
#endif
#include <sstream>
void print0x(int x)
{
	std::vector <int> vec;
	while(x)
	{
		vec.push_back(x&1);
		x>>=1;
	}
	std::reverse(vec.begin(),vec.end());
	for(int i=0;i<(int)vec.size();i++)
	{
		std::cout<<vec[i];
	}
	std::cout<<' ';
}

template <typename T>
void print0x(T x,int len)
{
	std::vector <int> vec;
	while(x)
	{
		std::cout<<(x&1);
		x>>=1;
		len--;
		// vec.push_back(x&1);
		// x>>=1;
	}
	while(len--) cout<<0;
	// reverse(vec.begin(),vec.end());
	// for(int i=(int)vec.size();i<len;i++)
	// {
	// 	putchar('0');
	// }
	// for(size_t i=0;i<vec.size();i++)
	// {
	// 	std::cout<<vec[i];
	// }
	// std::cout<<' ';
}
vector<string> vec_splitter(string s) {
	s += ',';
	vector<string> res;
	while(!s.empty()) {
		res.push_back(s.substr(0, s.find(',')));
		s = s.substr(s.find(',') + 1);
	}
	return res;
}
void debug_out(
vector<string> __attribute__ ((unused)) args,
__attribute__ ((unused)) int idx, 
__attribute__ ((unused)) int LINE_NUM) { cerr << endl; } 
template <typename Head, typename... Tail>
void debug_out(vector<string> args, int idx, int LINE_NUM, Head H, Tail... T) {
	if(idx > 0) cerr << ", "; else cerr << "Line(" << LINE_NUM << ") ";
	stringstream ss; ss << H;
	cerr << args[idx] << " = " << ss.str();
	debug_out(args, idx + 1, LINE_NUM, T...);
}
#define debug(...) debug_out(vec_splitter(#__VA_ARGS__), 0, __LINE__, __VA_ARGS__)
#endif
using namespace std;
int n;
vector<int> edges[200005];
int sz[200005];
int block[200005];
vector<int> v1,v2;

void calc(int x,int par,vector<int> &v)
{
	v.push_back(sz[x]);
	for(auto u:edges[x])
	{
		if(u==par) continue;
		calc(u,x,v);
	}
}

pii go(int x,int par)
{
	pii o=mp(n-sz[x],x);
	pii res=mp(inf,-1);
	for(auto u:edges[x])
	{
		if(u==par) continue;
		chmax(o.first,sz[u]);
		chmin(res,go(u,x));
	}
	chmin(res,o);
	return res;
}

void dfs(int x,int par)
{
	sz[x]=1;
	for(auto u:edges[x])
	{
		if(u==par) continue;
		dfs(u,x);
		sz[x]+=sz[u];
	}
}

int calc(int a,int b,int c)
{
	return max({a,b,c})-min({a,b,c});
}

int calc(const vector<int> &v1,const vector<int> &v2)
{
	int res=inf;
	for(int x:v1)
	{
		int m=n-x;
		int it=lower_bound(all(v2),m/2)-v2.begin();
		for(int i=max(it-5,0);i<min(it+5,(int)v2.size());i++)
		{
			chmin(res,calc(x,v2[i],m-v2[i]));
		}
	}
	return res;
}

vector<vector<int> > vv;
int main()
{
//	freopen("input.txt","r",stdin);
	cin>>n;
	for(int i=0;i<n-1;i++)
	{
		int x,y;
		scanf("%d%d",&x,&y);
		x--;
		y--;
		edges[x].emplace_back(y);
		edges[y].emplace_back(x);
	}
	dfs(0,-1);
	int rt=go(0,-1).second;
	dfs(rt,-1);
	sort(all(edges[rt]),[](int x,int y){return sz[x]>sz[y];});
	for(auto u:edges[rt])
	{
		vector<int> t;
		calc(u,rt,t);
		sort(all(t));
		vv.emplace_back(t);
	}
	int res=inf;
	chmin(res,calc(vv[0],vv[1]));
	int m=n-sz[edges[rt][0]];
	for(auto x:vv[0])
	{
		if(x==sz[edges[rt][0]]) continue;
		chmin(res,calc(m,x,m-x));
	}
	cout<<res<<endl;
	return 0;
}

Compilation message (stderr)

papricice.cpp: In function 'int main()':
papricice.cpp:404:8: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
  404 |   scanf("%d%d",&x,&y);
      |   ~~~~~^~~~~~~~~~~~~~

• Subtask 1: 15 / 15
• Subtask 2: 35 / 35
• Subtask 3: 60 / 60