Submission #640568

#	Time	Username	Problem	Language	Result	Execution time	Memory
640568		SanguineChameleon	Paprike (COI18_paprike)	C++17	100 / 100	54 ms	20308 KiB

paprike

// BEGIN BOILERPLATE CODE

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

#ifdef KAMIRULEZ
	const bool kami_loc = true;
	const long long kami_seed = 69420;
#else
	const bool kami_loc = false;
	const long long kami_seed = chrono::steady_clock::now().time_since_epoch().count();
#endif

const string kami_fi = "kamirulez.inp";
const string kami_fo = "kamirulez.out";
mt19937_64 kami_gen(kami_seed);

long long rand_range(long long rmin, long long rmax) {
	uniform_int_distribution<long long> rdist(rmin, rmax);
	return rdist(kami_gen);
}

void file_io(string fi, string fo) {
	if (fi != "" && (!kami_loc || fi == kami_fi)) {
		freopen(fi.c_str(), "r", stdin);
	}
	if (fo != "" && (!kami_loc || fo == kami_fo)) {
		freopen(fo.c_str(), "w", stdout);
	}
}

void set_up() {
	if (kami_loc) {
		file_io(kami_fi, kami_fo);
	}
	ios_base::sync_with_stdio(0);
	cin.tie(0);
}

void just_do_it();

void just_exec_it() {
	if (kami_loc) {
		auto pstart = chrono::steady_clock::now();
		just_do_it();
		auto pend = chrono::steady_clock::now();
		long long ptime = chrono::duration_cast<chrono::milliseconds>(pend - pstart).count();
		string bar(50, '=');
		cout << '\n' << bar << '\n';
		cout << "Time: " << ptime << " ms" << '\n';
	}
	else {
		just_do_it();
	}
}

int main() {
	set_up();
	just_exec_it();
	return 0;
}

// END BOILERPLATE CODE

// BEGIN MAIN CODE

const int ms = 1e5 + 20;
vector<int> adj[ms];
long long a[ms];
long long dp[ms];
int res = 0;
long long k;

void dfs(int u, int pr) {
	dp[u] = a[u];
	vector<long long> p;
	for (auto v: adj[u]) {
		if (v != pr) {
			dfs(v, u);
			p.push_back(dp[v]);
			res++;
		}
	}
	sort(p.begin(), p.end());
	for (auto x: p) {
		if (dp[u] + x <= k) {
			dp[u] += x;
			res--;
		}
	}
}

void just_do_it() {
	int n;
	cin >> n >> k;
	for (int i = 1; i <= n; i++) {
		cin >> a[i];
	}
	for (int i = 0; i < n - 1; i++) {
		int u, v;
		cin >> u >> v;
		adj[u].push_back(v);
		adj[v].push_back(u);
	}
	dfs(1, -1);
	cout << res;
}

// END MAIN CODE

Compilation message (stderr)

paprike.cpp: In function 'void file_io(std::string, std::string)':
paprike.cpp:25:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   25 |   freopen(fi.c_str(), "r", stdin);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
paprike.cpp:28:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   28 |   freopen(fo.c_str(), "w", stdout);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 11 / 11
• Subtask 2: 13 / 13
• Subtask 3: 27 / 27
• Subtask 4: 49 / 49