Submission #557851

#	Time	Username	Problem	Language	Result	Execution time	Memory
557851		Koosha_mv	Cats or Dogs (JOI18_catdog)	C++14	38 / 100	3051 ms	28196 KiB

catdog

#include <bits/stdc++.h>
using namespace std;
#define dbgv(v) cout<<#v<<" = "; f(i,0,v.size()) cout<<v[i]<<" "; cout<<endl
#define dbga(a,x,y) cout<<#a<<" = "; f(i,x,y) cout<<a[i]<<" "; cout<<endl
#define erorp(x) cout<<#x<<"={"<<x.F<<" , "<<x.S<<"}"<<endl
#define eror(x) cout<<#x<<'='<<(x)<<endl
#define f_(i,a,b) for(int i=a;i>=b;i--)
#define f(i,a,b) for(int i=a;i<b;i++)
#define nb(x) __builtin_popcount(x)
#define all(v) v.begin(),v.end()
#define bit(n,k) (((n)>>(k))&1)
#define Add(x,y) x=(x+y)%mod
#define maxm(a,b) a=max(a,b)
#define minm(a,b) a=min(a,b)
#define lst(x) x[x.size()-1]
#define sz(x) int(x.size())
#define mp make_pair
#define ll long long
#define pb push_back
#define S second
#define F first
//#include "catdog.h"

const int N=1e6+99;

int n,ans,a[N],dp[N];
vector<int> g[N];

void initialize(int _n,vector<int> A,vector<int> B){
	n=_n;
	f(i,0,n-1) g[A[i]].pb(B[i]),g[B[i]].pb(A[i]);		
}
void dfs1(int u,int p){
	int cnt1=0,cnt2=0;
	dp[u]=0;
	for(auto v : g[u]){
		if(v==p) continue ;
		dfs1(v,u);
		cnt1+=(dp[v]==1);
		cnt2+=(dp[v]==2);
	}
	if(a[u]==0){
		ans+=min(cnt1,cnt2);
		if(cnt1>cnt2) dp[u]=1;
		if(cnt2>cnt1) dp[u]=2;
	}
	if(a[u]==1){
		ans+=cnt2;
		dp[u]=1;
	}
	if(a[u]==2){
		ans+=cnt1;
		dp[u]=2;
	}
}
int solve(){
	ans=0;
	dfs1(1,1);
	return ans;
}
int cat(int u){
	a[u]=1;	
	return solve();
}
int dog(int u){
	a[u]=2;
	return solve();
}
int neighbor(int u){
	a[u]=0;
	return solve();
}
/*
int32_t main(){
	ios:: sync_with_stdio(0), cin.tie(0), cout.tie(0);
	vector<int> A,B;
	int n,q;
	cin>>n;
	f(i,1,n){
		int u,v;
		cin>>u>>v;
		A.pb(u);
		B.pb(v);
	}
	initialize(n,A,B);
	cin>>q;
	while(q--){
		int t,u;
		cin>>t>>u;
		if(t==1) cout<<cat(u)<<endl;
		if(t==2) cout<<dog(u)<<endl;
		if(t==3) cout<<neighbor(u)<<endl;
	}
}*/
/*
5
1 2
2 3
2 4
4 5
3
1 3
2 5
2 1

5
1 2
2 3
2 4
4 5
5
1 3
2 5
1 2
2 1
3 2
*/

• Subtask 1: 8 / 8
• Subtask 2: 30 / 30
• Subtask 3: 0 / 62