Submission #315249

#	Time	Username	Problem	Language	Result	Execution time	Memory
315249		shrek12357	Triumphal arch (POI13_luk)	C++14	100 / 100	1329 ms	26088 KiB

luk

#include <iostream>
#include <vector>
#include <algorithm>
#include <string>
#include <map>
#include <set>
#include <climits>
#include <cmath>
#include <fstream>
#include <queue>
#include <stack>
#include <bitset>
using namespace std;
#define ll long long
//cin.tie(0);ios_base::sync_with_stdio(0); 

const int MAXN = 3 * 1e5 + 5;
vector<int> adjList[MAXN];
int par[MAXN];
int n;
int good;

void dfs(int src) {
	for (auto i : adjList[src]) {
		if (i == par[src]) {
			continue;
		}
		par[i] = src;
		dfs(i);
	}
}

int check(int src, int mid) {
	int cur = 0;
	for (auto i : adjList[src]) {
		if (i == par[src]) {
			continue;
		}
		cur += check(i, mid) + 1;
	}
	cur -= mid;
	return max(0, cur);
}

int main() {
	cin >> n;
	par[0] = 0;
	for (int i = 0; i < n - 1; i++) {
		int a, b;
		cin >> a >> b;
		a--;
		b--;
		adjList[a].push_back(b);
		adjList[b].push_back(a);
	}
	dfs(0);
	int lo = 0, hi = n;
	while (lo < hi) {
		int mid = (lo + hi) / 2;
		good = true;
		if (check(0, mid) == 0) {
			hi = mid;
		}
		else {
			lo = mid + 1;
		}
	}
	cout << lo << endl;
}

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 10 / 10
• Subtask 4: 10 / 10
• Subtask 5: 10 / 10
• Subtask 6: 10 / 10
• Subtask 7: 10 / 10
• Subtask 8: 10 / 10
• Subtask 9: 10 / 10
• Subtask 10: 10 / 10