Submission #765876

#	Time	Username	Problem	Language	Result	Execution time	Memory
765876		khshg	Meetings (IOI18_meetings)	C++14	0 / 100	1 ms	340 KiB

meetings

#include<bits/stdc++.h>
using namespace std;
 
using ll = long long;
using ld = long double;
using str = string;
 
using pi = pair<int, int>;
using pl = pair<ll, ll>;
using pd = pair<ld, ld>;
#define mp make_pair
#define ff first
#define ss second
 
#define ar array
template<class T> using V = vector<T>;
using vi = V<int>;
using vb = V<bool>;
using vl = V<ll>;
using vd = V<ld>;
using vs = V<str>;
using vpi = V<pi>;
using vpl = V<pl>;
using vpd = V<pd>;
 
#define sz(x) (int)((x).size())
#define bg(x) begin(x)
#define all(x) bg(x), end(x)
#define rall(x) (x).rbegin(), (x).rend()
#define sor(x) sort(all(x))
#define rsz resize
#define ins insert
#define pb push_back
#define eb emplace_back
#define ft front()
#define bk back()
#define lb lower_bound
#define ub upper_bound
 
#define FOR(i, a, b) for(int i = (a); i < (b); ++i)
#define F0R(i, a) FOR(i, 0, a)
#define ROF(i, a, b) for(int i = (b) - 1; i >= (a); --i)
#define R0F(i, a) ROF(i, 0, a)
#define rep(a) F0R(_, a)
#define trav(a, x) for(auto& a : x)
 
template<class T> bool ckmin(T& a, const T& b) { return (b < a ? a = b, 1 : 0); }
template<class T> bool ckmax(T& a, const T& b) { return (b > a ? a = b, 1 : 0); }

const ll INF = 0x3f3f3f3f3f3f3f3f;

template<typename T>
struct Sparse_Table {
	int lgflr(int x) {
		return 31 - __builtin_clz(x);
	}
	T f(T x, T y) { // implement !!!
		return max(x, y);
	}
	int N, K;
	vector<vector<T>> st;
	void init(vector<T> a) {
		N = (int) a.size();
		K = lgflr(N);
		st = vector<vector<T>>(K + 1, vector<T>(N));
		swap(st[0], a);
		for(int i = 1; i <= K; ++i) {
			for(int j = 0; j + (1 << i) <= N; ++j) {
				st[i][j] = f(st[i - 1][j], st[i - 1][j + (1 << (i - 1))]);
			}
		}
	}
	T query(int L, int R) {
		assert(L >= 0 && R >= 0);
		int i = lgflr(R - L + 1);
		return f(st[i][L], st[i][R - (1 << i) + 1]);
	}
};
 
vl minimum_costs(vi H, vi L, vi R) {
	int N = sz(H);
	vpi is;
	F0R(i, N) {
		if(H[i] == 2) continue;
		int j = i;
		while(j + 1 < N && H[j + 1] == 1) {
			++j;
		}
		is.eb(i, j);
		i = j;
	}
	vi K(sz(is));
	F0R(i, sz(is)) K[i] = is[i].ss - is[i].ff + 1;
	Sparse_Table<int> mx;
	mx.init(K);
	int Q = sz(L);
	vl ans(Q);
	F0R(q, Q) {
		int l;
		{
			int tl = 0, tr = sz(is) - 1;
			l = -1;
			while(tl <= tr) {
				int tm = (tl + tr) / 2;
				if(is[tm].ff < L[q]) {
					l = tm;
					tl = tm + 1;
				} else {
					tr = tm - 1;
				}
			}
		}
		if(l != -1 && is[l].ss >= L[q]) ckmax(ans[q], (ll)is[l].ss - L[q] + 1);
		++l;
		int r;
		{
			int tl = 0, tr = sz(is) - 1;
			l = tr + 1;
			while(tl <= tr) {
				int tm = (tl + tr) / 2;
				if(is[tm].ss > R[q]) {
					r = tm;
					tr = tm - 1;
				} else {
					tl = tm + 1;
				}
			}
		}
		if(r < sz(is) && is[r].ff <= R[q]) ckmax(ans[q], (ll)min(R[q] - is[r].ff + 1, is[r].ss - is[r].ff + 1));
		--r;
		if(l <= r) ckmax(ans[q], (ll)mx.query(l, r));
		ckmin(ans[q], (ll)(R[q] - L[q] + 1));
		ans[q] = 2 * (R[q] - L[q] + 1 - ans[q]) + ans[q];
	}
	return ans;
}

Compilation message (stderr)

meetings.cpp: In function 'vl minimum_costs(vi, vi, vi)':
meetings.cpp:129:24: warning: 'r' may be used uninitialized in this function [-Wmaybe-uninitialized]
  129 |   if(r < sz(is) && is[r].ff <= R[q]) ckmax(ans[q], (ll)min(R[q] - is[r].ff + 1, is[r].ss - is[r].ff + 1));
      |                        ^

• Subtask 1: 0 / 4
• Subtask 2: 0 / 15
• Subtask 3: 0 / 17
• Subtask 4: 0 / 24
• Subtask 5: 0 / 40