Submission #879761

#	Time	Username	Problem	Language	Result	Execution time	Memory
879761		TAhmed33	Papričice (COCI20_papricice)	C++98	50 / 110	1035 ms	25684 KiB

papricice

#include <bits/stdc++.h>
using namespace std;
const int MAXN = 2e5 + 25;
vector <int> adj[MAXN];
int sze[MAXN], n, in[MAXN], out[MAXN], t;
set <int> dd[MAXN];
typedef long long ll;
int mn = 1e9; const int bad = -1e9;
void dfs (int pos, int par) {
	sze[pos] = 1;
	in[pos] = ++t;
    int mx = bad;
	for (auto j : adj[pos]) {
		if (j == par) continue;
		dfs(j, pos);
		sze[pos] += sze[j];
        if (dd[pos].size() < dd[j].size()) swap(dd[pos], dd[j]);
        for (auto i : dd[j]) dd[pos].insert(i);
        dd[j].clear();
	}
    dd[pos].insert(sze[pos]);
    for (auto i : dd[pos]) {
        if (abs(2 * i - sze[pos]) < abs(2 * mx - sze[pos])) {
            mx = i;
        }
    }
    if (sze[pos] != 1 && pos != 1) mn = min(mn, max({n - sze[pos], sze[pos] - mx, mx}) - min({n - sze[pos], sze[pos] - mx, mx}));
	out[pos] = t;
}
bool check (int x, int y) {
	return in[y] < in[x] && in[x] <= out[y];
}
int main () {
	cin >> n;
	for (int i = 1; i < n; i++) {
		int a, b;
		cin >> a >> b;
		adj[a].push_back(b);
		adj[b].push_back(a);
	}
	dfs(1, -1);
	for (int i = 2; i <= n; i++) {
		for (int j = i + 1; j <= n; j++) {
            if (check(i, j) || check(j, i)) continue;
			int x = n - sze[j] - sze[i];
			mn = min(mn, max({sze[i], sze[j], x}) - min({sze[i], sze[j], x}));	
		}
	}
	cout << mn << '\n';
}

• Subtask 1: 15 / 15
• Subtask 2: 35 / 35
• Subtask 3: 0 / 60