oj.uz

답안 #146743

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
146743 2019-08-25T19:34:42 Z abacaba 관광지 (IZhO14_shymbulak) C++14
100 / 100
 348 ms 21756 KB 
#include <iostream>
#include <string>
#include <cstring>
#include <vector>
#include <map>
#include <set>
#include <algorithm>
#include <math.h>
#include <cstdio>
#include <stdio.h>
#include <queue>
#include <deque>
using namespace std;

#define max3(a, b, c) max(a, max(b, c))
#define min3(a, b, c) min(a, min(b, c))
#define mp make_pair
#define f first
#define se second
#define pb push_back
#define ppb pop_back
#define ll long long
#define ull unsigned long long
#define cntbit(x) __builtin_popcount(x)
#define endl '\n'
#define uset unordered_set
#define umap unordered_map
#define pii pair<long long, long long>
#define ld long double
#define pll pair<long long, long long>

#define int long long

const int inf = 2e9;
const int N = 2e5 + 15;
int n, mx, parent[N], sz;
pii d[N], ans;
vector <int> g[N], cycle;
bool used[N], is[N];
map <int, int> cnt;
multiset <int> cur;

bool find_cycle(int v, int p = -1) {
	used[v] = true;
	parent[v] = p;
	for(int to : g[v]) {
		if(to != p) {
			if(used[to]) {
				int u = v;
				is[u] = true;
				cycle.pb(u);
				while(u != to) {
					u = parent[u];
					cycle.pb(u);
					is[u] = true;
				}
				return true;
			}
			else if(find_cycle(to, v))
				return true;
		}
	}
	return false;
}

inline void combine(pii &a, pii b) {
	if(a.f == b.f)
		a.se += b.se;
	else if(a.f < b.f)
		a = b;
}

void dfs_tree(int v, int p = -1) {
	d[v] = mp(0, 1);
	for(int to : g[v])
		if(to != p && !is[to]) {
			dfs_tree(to, v);
			++d[to].f;
			combine(ans, mp(d[v].first + d[to].first, d[v].second * d[to].second));
			combine(d[v], d[to]);
		}
}

#undef int

int main() {
	#define int long long
	cin >> n;
	for(int i = 1; i <= n; ++i) {
		int u, v;
		cin >> u >> v;
		g[u].pb(v);
		g[v].pb(u);
	}
	find_cycle(1);
	sz = cycle.size();
	for(int i : cycle)
		dfs_tree(i);
	for(int i = 0; i < sz + sz/2; ++i) {
		if(i >= sz/2)
			combine(ans, mp(d[cycle[i % sz]].f + i + *cur.rbegin(), 0)),
			cur.erase(cur.find(d[cycle[i - sz/2]].f - i + sz/2));
		cur.insert(d[cycle[i % sz]].f - i);
	}
	for(int i = 0; i < sz + sz/2; ++i) {
		if(i >= sz / 2)
			ans.se += d[cycle[i % sz]].se * cnt[ans.f - d[cycle[i % sz]].f - i],
			cnt[d[cycle[i - sz/2]].f - i + sz/2] -= d[cycle[i - sz/2]].se;
		cnt[d[cycle[i % sz]].f - i] += d[cycle[i % sz]].se;
	}
	cout << ans.se << endl;
	return 0;
}

Subtask #1
30.0 / 30.0

# 결과 실행 시간 메모리 Grader output
1 Correct 6 ms 4984 KB Output is correct
2 Correct 6 ms 5112 KB Output is correct
3 Correct 7 ms 4984 KB Output is correct
4 Correct 8 ms 5112 KB Output is correct
5 Correct 7 ms 5084 KB Output is correct
6 Correct 8 ms 5084 KB Output is correct
7 Correct 6 ms 5112 KB Output is correct
8 Correct 6 ms 5112 KB Output is correct
9 Correct 6 ms 5112 KB Output is correct
10 Correct 6 ms 5112 KB Output is correct
11 Correct 6 ms 4984 KB Output is correct
12 Correct 10 ms 5112 KB Output is correct
13 Correct 6 ms 4984 KB Output is correct
14 Correct 8 ms 5112 KB Output is correct
15 Correct 7 ms 5112 KB Output is correct

Subtask #2
20.0 / 20.0

# 결과 실행 시간 메모리 Grader output
1 Correct 7 ms 5240 KB Output is correct
2 Correct 7 ms 5172 KB Output is correct
3 Correct 7 ms 5240 KB Output is correct
4 Correct 7 ms 5112 KB Output is correct
5 Correct 12 ms 5340 KB Output is correct
6 Correct 11 ms 5368 KB Output is correct
7 Correct 13 ms 5368 KB Output is correct
8 Correct 12 ms 5368 KB Output is correct
9 Correct 12 ms 5496 KB Output is correct
10 Correct 11 ms 5368 KB Output is correct

Subtask #3
50.0 / 50.0

# 결과 실행 시간 메모리 Grader output
1 Correct 148 ms 12288 KB Output is correct
2 Correct 145 ms 12664 KB Output is correct
3 Correct 174 ms 21756 KB Output is correct
4 Correct 132 ms 12244 KB Output is correct
5 Correct 127 ms 12024 KB Output is correct
6 Correct 317 ms 19376 KB Output is correct
7 Correct 219 ms 15856 KB Output is correct
8 Correct 278 ms 19264 KB Output is correct
9 Correct 348 ms 18992 KB Output is correct
10 Correct 265 ms 21412 KB Output is correct
11 Correct 257 ms 19428 KB Output is correct
12 Correct 271 ms 20196 KB Output is correct