답안 #736169

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
736169 2023-05-05T09:22:30 Z marvinthang Papričice (COCI20_papricice) C++17
110 / 110
188 ms 21576 KB
/*************************************
*    author: marvinthang             *
*    created: 05.05.2023 15:57:36    *
*************************************/

#include <bits/stdc++.h>

using namespace std;

#define                  fi  first
#define                  se  second
#define                left  ___left
#define               right  ___right
#define                TIME  (1.0 * clock() / CLOCKS_PER_SEC)
#define             MASK(i)  (1LL << (i))
#define           BIT(x, i)  ((x) >> (i) & 1)
#define  __builtin_popcount  __builtin_popcountll
#define              ALL(v)  (v).begin(), (v).end()
#define           REP(i, n)  for (int i = 0, _n = (n); i < _n; ++i)
#define          REPD(i, n)  for (int i = (n); i--; )
#define        FOR(i, a, b)  for (int i = (a), _b = (b); i < _b; ++i) 
#define       FORD(i, b, a)  for (int i = (b), _a = (a); --i >= _a; ) 
#define       FORE(i, a, b)  for (int i = (a), _b = (b); i <= _b; ++i) 
#define      FORDE(i, b, a)  for (int i = (b), _a = (a); i >= _a; --i) 
#define        scan_op(...)  istream & operator >> (istream &in, __VA_ARGS__ &u)
#define       print_op(...)  ostream & operator << (ostream &out, const __VA_ARGS__ &u)
#ifdef LOCAL
    #include "debug.h"
#else
    #define file(name) if (fopen(name".inp", "r")) { freopen(name".inp", "r", stdin); freopen(name".out", "w", stdout); }
    #define DB(...) 23
    #define db(...) 23
    #define debug(...) 23
#endif

template <class U, class V> scan_op(pair <U, V>)  { return in >> u.first >> u.second; }
template <class T> scan_op(vector <T>)  { for (size_t i = 0; i < u.size(); ++i) in >> u[i]; return in; }
template <class U, class V> print_op(pair <U, V>)  { return out << '(' << u.first << ", " << u.second << ')'; }
template <size_t i, class T> ostream & print_tuple_utils(ostream &out, const T &tup) { if constexpr(i == tuple_size<T>::value) return out << ")";  else return print_tuple_utils<i + 1, T>(out << (i ? ", " : "(") << get<i>(tup), tup); }
template <class ...U> print_op(tuple<U...>) { return print_tuple_utils<0, tuple<U...>>(out, u); }
template <class Con, class = decltype(begin(declval<Con>()))> typename enable_if <!is_same<Con, string>::value, ostream&>::type operator << (ostream &out, const Con &con) { out << '{'; for (__typeof(con.begin()) it = con.begin(); it != con.end(); ++it) out << (it == con.begin() ? "" : ", ") << *it; return out << '}'; }
template <class A, class B> bool minimize(A &a, B b)  { if (a > b) { a = b; return true; } return false; }
template <class A, class B> bool maximize(A &a, B b)  { if (a < b) { a = b; return true; } return false; }

// end of template

const int MAX = 2e5 + 5;
const int INF = 1e9;

int N, treeSize[MAX], res = INF;
vector <int> adj[MAX];

void init(void) {
	cin >> N;
	FOR(i, 1, N) {
		int u, v; cin >> u >> v;
		adj[u].push_back(v);
		adj[v].push_back(u);
	}
}

void dfs(int u, int par) {
	treeSize[u] = 1;
	for (int v: adj[u]) if (v != par) {
		dfs(v, u);
		treeSize[u] += treeSize[v];
	}
}

set <int> in, out;

int get_val(int a, int b, int c) {
	return max({a, b, c}) - min({a, b, c});
}

void dfs2(int u, int par) {
	auto it = in.upper_bound((N + treeSize[u]) / 2);
	if (it != in.end()) minimize(res, get_val(treeSize[u], N - *it, *it - treeSize[u]));
	if (it != in.begin()) {
		--it;
		minimize(res, get_val(treeSize[u], N - *it, *it - treeSize[u]));
	}
	it = out.upper_bound((N - treeSize[u]) / 2);
	if (it != out.end()) minimize(res, get_val(treeSize[u], N - *it - treeSize[u], *it));
	if (it != out.begin()) {
		--it;
		minimize(res, get_val(treeSize[u], N - *it - treeSize[u], *it));
	}

	in.insert(treeSize[u]);
	for (int v: adj[u]) if (v != par) dfs2(v, u);
	in.erase(treeSize[u]);
	out.insert(treeSize[u]);
}

void process(void) {
	dfs(1, 0);
	dfs2(1, 0);
	cout << res << '\n';
}

int main(void) {
	ios_base::sync_with_stdio(false); cin.tie(nullptr); // cout.tie(nullptr);
	file("coci2021_r1_papricice");
	init();
	process();
	// cerr << "Time elapsed: " << TIME << " s.\n";
	return (0^0);
}

Compilation message

papricice.cpp: In function 'int main()':
papricice.cpp:30:61: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   30 |     #define file(name) if (fopen(name".inp", "r")) { freopen(name".inp", "r", stdin); freopen(name".out", "w", stdout); }
      |                                                      ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
papricice.cpp:104:2: note: in expansion of macro 'file'
  104 |  file("coci2021_r1_papricice");
      |  ^~~~
papricice.cpp:30:94: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   30 |     #define file(name) if (fopen(name".inp", "r")) { freopen(name".inp", "r", stdin); freopen(name".out", "w", stdout); }
      |                                                                                       ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
papricice.cpp:104:2: note: in expansion of macro 'file'
  104 |  file("coci2021_r1_papricice");
      |  ^~~~
# 결과 실행 시간 메모리 Grader output
1 Correct 3 ms 4948 KB Output is correct
2 Correct 3 ms 5028 KB Output is correct
3 Correct 3 ms 4948 KB Output is correct
4 Correct 3 ms 4948 KB Output is correct
5 Correct 3 ms 4948 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 3 ms 4948 KB Output is correct
2 Correct 3 ms 5028 KB Output is correct
3 Correct 3 ms 4948 KB Output is correct
4 Correct 3 ms 4948 KB Output is correct
5 Correct 3 ms 4948 KB Output is correct
6 Correct 4 ms 5076 KB Output is correct
7 Correct 4 ms 5076 KB Output is correct
8 Correct 5 ms 5076 KB Output is correct
9 Correct 4 ms 5076 KB Output is correct
10 Correct 4 ms 5076 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 3 ms 4948 KB Output is correct
2 Correct 3 ms 5028 KB Output is correct
3 Correct 3 ms 4948 KB Output is correct
4 Correct 3 ms 4948 KB Output is correct
5 Correct 3 ms 4948 KB Output is correct
6 Correct 4 ms 5076 KB Output is correct
7 Correct 4 ms 5076 KB Output is correct
8 Correct 5 ms 5076 KB Output is correct
9 Correct 4 ms 5076 KB Output is correct
10 Correct 4 ms 5076 KB Output is correct
11 Correct 186 ms 14772 KB Output is correct
12 Correct 188 ms 14732 KB Output is correct
13 Correct 136 ms 15096 KB Output is correct
14 Correct 149 ms 14844 KB Output is correct
15 Correct 183 ms 14684 KB Output is correct
16 Correct 99 ms 14600 KB Output is correct
17 Correct 148 ms 14668 KB Output is correct
18 Correct 183 ms 21576 KB Output is correct
19 Correct 151 ms 14792 KB Output is correct
20 Correct 156 ms 14756 KB Output is correct