제출 #1059971

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1059971		Tob	Sky Walking (IOI19_walk)	C++14	100 / 100	2339 ms	171960 KiB

walk

#include <bits/stdc++.h>

#include "walk.h"

#define F first
#define S second
#define all(x) x.begin(), x.end()
#define pb push_back
#define FIO ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0)

using namespace std;

typedef long long ll;
typedef pair <ll, ll> pii;
typedef vector <int> vi;

const int N = 1e5 + 7;
const ll inf = 1e18;

ll dis[6*N];
map <int, int> ma[N];
map <int, set <int> > se;
vector <int> ad[N], re[N];
vector <pii> adj[6*N];

inline void Edge(int x, int y, int w) {
	adj[x].pb({y, w});
	adj[y].pb({x, w});
}

ll min_distance(vi x, vi h, vi l, vi r, vi y, int sta, int en) {
	int n = x.size(), m = l.size();
	vector <int> v, gl(n, -1), gr(n, -1);
	stack <int> st;
	for (int i = 0; i < n; i++) {
		while (!st.empty() && h[st.top()] <= h[i]) st.pop();
		if (!st.empty()) gl[i] = st.top();
		st.push(i);
	}
	while (!st.empty()) st.pop();
	for (int i = n-1; i >= 0; i--) {
		while (!st.empty() && h[st.top()] <= h[i]) st.pop();
		if (!st.empty()) gr[i] = st.top();
		st.push(i);
	}
	
	auto Do = [&](int z) {
		v.clear();
		for (int i = 0; i < m; i++) if (l[i] < z && z < r[i] && y[i] <= h[z]) {
			l.pb(z);
			r.pb(r[i]);
			y.pb(y[i]);
			r[i] = z;
		}
		
		m = l.size();
		for (int i = 0; i < m; i++) if (l[i] < z && z < r[i] && y[i] > h[z]) v.pb(i);
		sort(all(v), [&](int a, int b) {return y[a] < y[b];});
		
		int le = z, ri = z;
		for (int i = 0; i < v.size(); i++) {
			while (h[le] < y[v[i]]) le = gl[le];
			while (h[ri] < y[v[i]]) ri = gr[ri];
			if (le != l[v[i]]) {
				l.pb(l[v[i]]);
				r.pb(le);
				y.pb(y[v[i]]);
			}
			if (ri != r[v[i]]) {
				l.pb(ri);
				r.pb(r[v[i]]);
				y.pb(y[v[i]]);
			}
			l[v[i]] = le;
			r[v[i]] = ri;
		}
		m = l.size();
	};
	
	Do(sta);
	Do(en);
	
	int cnt = 0;
	ma[sta][0] = cnt++;
	ma[en][0] = cnt++;
	for (int i = 0; i < m; i++) {
		if (ma[l[i]].find(y[i]) == ma[l[i]].end()) ma[l[i]][y[i]] = cnt++;
		if (ma[r[i]].find(y[i]) == ma[r[i]].end()) ma[r[i]][y[i]] = cnt++;
		ad[l[i]].pb(y[i]);
		re[r[i]].pb(y[i]);
		se[y[i]].insert(l[i]);
		se[y[i]].insert(r[i]);
	}
	
	multiset <int> t;
	t.insert(0);
	for (int i = 0; i < n; i++) {
		for (auto it : ad[i]) t.insert(it);
		auto down = [&](int it) {
			int z = *(--t.lower_bound(it));
			if (ma[i].find(z) == ma[i].end()) ma[i][z] = cnt++;
			Edge(ma[i][it], ma[i][z], it-z);
			se[z].insert(i);
		};
		for (auto it : ad[i]) down(it);
		for (auto it : re[i]) down(it);
		for (auto it : re[i]) t.erase(t.find(it));
	}
	
	for (int i = 0; i < m; i++) {
		auto p = se[y[i]].find(l[i]);
		int la = l[i]; ++p;
		while (p != se[y[i]].end() && *p <= r[i]) {
			Edge(ma[la][y[i]], ma[*p][y[i]], x[*p]-x[la]);
			la = *p;
			++p;
		}
	}
	
	for (int i = 1; i < cnt; i++) dis[i] = inf;
	set <pii> s;
	s.insert({0, 0});
	while (!s.empty()) {
		auto p = s.begin();
		int xx = p->S;
		s.erase(p);
		for (auto yy : adj[xx]) {
			if (dis[xx] + yy.S < dis[yy.F]) {
				if (dis[yy.F] != inf) s.erase({dis[yy.F], yy.F});
				dis[yy.F] = dis[xx] + yy.S;
				s.insert({dis[yy.F], yy.F});
			}
		}
	}
	if (dis[1] == inf) return -1;
	return dis[1];
}

컴파일 시 표준 에러 (stderr) 메시지

walk.cpp: In lambda function:
walk.cpp:61:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   61 |   for (int i = 0; i < v.size(); i++) {
      |                   ~~^~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 14 / 14
• Subtask 3: 15 / 15
• Subtask 4: 18 / 18
• Subtask 5: 43 / 43