Submission #710707

#	Time	Username	Problem	Language	Result	Execution time	Memory
710707		aVe	Papričice (COCI20_papricice)	C++14	110 / 110	222 ms	22480 KiB

papricice

#include <bits/stdc++.h>
#define ll long long
#define pii pair<int,int>
#define pll pair<ll,ll>
#define vi vector<int>
#define vl vector<ll>
#define mp make_pair
#define pb push_back
#define se second
#define fi first
using namespace std;
void __print(int x) {cerr << x;}
void __print(long x) {cerr << x;}
void __print(long long x) {cerr << x;}
void __print(unsigned x) {cerr << x;}
void __print(unsigned long x) {cerr << x;}
void __print(unsigned long long x) {cerr << x;}
void __print(float x) {cerr << x;}
void __print(double x) {cerr << x;}
void __print(long double x) {cerr << x;}
void __print(char x) {cerr << '\'' << x << '\'';}
void __print(const char *x) {cerr << '\"' << x << '\"';}
void __print(const string &x) {cerr << '\"' << x << '\"';}
void __print(bool x) {cerr << (x ? "true" : "false");}

template<typename T, typename V>
void __print(const pair<T, V> &x) {cerr << '{'; __print(x.first); cerr << ','; __print(x.second); cerr << '}';}
template<typename T>
void __print(const T &x) {int f = 0; cerr << '{'; for (auto &i: x) cerr << (f++ ? "," : ""), __print(i); cerr << "}";}
void _print() {cerr << "]\n";}
template <typename T, typename... V>
void _print(T t, V... v) {__print(t); if (sizeof...(v)) cerr << ", "; _print(v...);}
#ifndef ONLINE_JUDGE
#define debug(x...) cerr << "[" << #x << "] = ["; _print(x)
#else
#define debug(x...)
#endif
clock_t startTime;
double getCurrentTime() {
	return (double)(clock() - startTime) / CLOCKS_PER_SEC;
}
ll set_on(ll n, ll k){
	return (n |= 1 << k);
}
ll set_off(ll n, ll k){
	return (n &= ~(1UL << k));
}
bool check_bit(ll n, ll k){
	int bit = (n >> k) & 1U;
	if(bit == 1)
		return true;
	return false;
}
int n, ans = 1e9;
vi G[200100], sz;
void dfs(int at, int prev){
	sz[at] = 1;
	for(auto next : G[at]){
		if(next == prev)	continue;
		dfs(next, at);
		sz[at] += sz[next];
	}
}
set<int> A, B;
int opt(int a, int b, int c){
	return max({a, b, c}) - min({a, b, c});
}
vi close(set<int>&s, int x){
	vi v;
	auto it = s.lower_bound(x);
	if(it != s.end())v.pb(*it);
	if(it != s.begin()){
		--it;
		v.pb(*it);
	}
	return v;
}
void dfs2(int at, int prev){
	for(int szA : close(A, (n + sz[at]) / 2))
		ans = min(ans, opt(sz[at], szA - sz[at], n - szA));
	for(int szB : close(B, (n - sz[at]) / 2))
		ans = min(ans, opt(sz[at], szB, n - sz[at] - szB));
		
	A.insert(sz[at]);
	for(auto next : G[at])
		if(next != prev)
			dfs2(next, at);
			
	A.erase(sz[at]);
	B.insert(sz[at]);
}
void solve(){
	cin>>n;
	sz.resize(n);
	vector<pii> edge;
	for(int i = 1; i < n; i++){
		int a, b;
		cin>>a>>b;
		a--; b--;
		G[a].pb(b);
		G[b].pb(a);
	}
	dfs(0, -1);
	dfs2(0, -1);
	cout<<ans<<endl;
}
int main(){
	ios_base::sync_with_stdio(false);
	cin.tie(nullptr);
	cout.precision(10);
	cout<<fixed;
	startTime = clock();
	int t=1;
//	cin>>t;
	while(t--)
		solve();

	return 0;
}

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