제출 #1252562

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1252562		thdh__	Power Plant (JOI20_power)	C++20	100 / 100	112 ms	26800 KiB

power

#include <bits/stdc++.h>
#define ll long long
#define pb push_back
#define eb emplace_back
#define pu push
#define ins insert
#define fi first
#define se second
#define all(a) a.begin(),a.end()
#define bruh ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);
#define fu(x,a,b) for (auto x=a;x<=b;x++)
#define fd(x,a,b) for (auto x=a;x>=b;x--)
#define int ll

using namespace std;
//mt19937 mt(chrono::steady_clock::now().time_since_epoch().count());

/*
Competitive Programming notes that I need to study & fix my dumbass self:

1. Coding:
- Always be sure to check the memory of arrays (maybe use vectors), for loops
- Always try to maximize the memory if possible, even if you are going for subtasks
- Do not exploit #define int long long, it will kill you

2. Stress: 
- Always try generating big testcases and try if they run

3. Time management:
- Don't overcommit or undercommit, always spend a certain amount of time to think a problem, don't just look at it and say I'm fucked
- Do not spend too much time coding brute-force solutions, they should be easily-codable solutions that don't take up too much time

Time management schedule:
Offline / LAH days (4 problems - 3h):
15' thinking of solution / idea
1. no idea: skip
2. yes idea: continue thinking for <= 15'

+ implementing: <= 20'
+ brute-force: <= 5'
+ test generator: <= 5'

I hate offline because I am dumb
*/

typedef pair<int, int> ii;
const int N = 2e5+5;
const int B = 750;
const int mod = 1e9+7;
const int inf = 1e18;
using cd = complex<double>;
const long double PI = acos(-1);
int power(int a,int b) {ll x = 1;if (a >= mod) a%=mod; while (b) {if (b & 1) x = x*a % mod;a = a*a % mod;b>>=1;}return x;} 

int n;
bool check[N];
vector<int> adj[N];
int dp[N];
int ans = 0;

void dfs(int u, int p) 
{
	int mx = 0;
	for (auto v : adj[u]) 
	{
		if (v == p) continue;
		dfs(v, u);
		dp[u] += dp[v];
		mx = max(mx, dp[v]);
	}
	if (check[u]) dp[u] = max(dp[u]-1, 1ll);
	ans = max({ans, dp[u], mx+check[u]});
}


void solve()
{
	cin>>n;
	for (int i = 1; i < n; i++) 
	{
		int u,v; cin>>u>>v;
		adj[u].pb(v); adj[v].pb(u);
	}
	int cnt = 0;
	for (int i = 1; i <= n; i++) 
	{
		char c; cin>>c;
		if (c == '1') check[i] = 1, cnt++;
	}
	dfs(1, 0);
	cout<<ans;
}

/*
Go through the mistakes you usually make and revise your code, for god's sake...
*/

signed main()
{
	bruh
	//freopen("input.inp","r",stdin);
	//freopen("output.inp","w",stdout);
	int t = 1;
	// cin>>t;
	while (t--)
	{
		solve();
		cout<<"\n";
	}
}

• Subtask 1: 6 / 6
• Subtask 2: 41 / 41
• Subtask 3: 53 / 53