oj.uz

Submission #258112

# Submission time Handle Problem Language Result Execution time Memory
258112 2020-08-05T11:27:33 Z atoiz Sky Walking (IOI19_walk) C++14
15 / 100
 1045 ms 81480 KB 
#include "walk.h"
#include <iostream>
#include <vector>
#include <algorithm>
#include <cstdio>
#include <cmath>
#include <tuple>
#include <cassert>
#include <numeric>
 
using namespace std;
using ll = long long;
 
const int MAXY = 1000100100;
const ll INFLL = 1e16;
int N, M, T;
vector<int> X, H, L, R, Y;
vector<int> valY;
 
int dist(int i, int j) { return abs(X[i] - X[j]); }
// int pos(int y) { return (int) (upper_bound(valY.begin(), valY.end(), y) - valY.begin() - 1); } // first <=
 
struct SegmentTree {
	vector<ll> lazy, arr;
	vector<int> cnt;
	SegmentTree(): lazy((T + 2) * 4, INFLL), arr((T + 2) * 4, INFLL), cnt((T + 2) * 4, 0) {}
 
	void push(int rt, int lo, int hi) {
		if (lazy[rt] != INFLL && cnt[rt]) {
			if (lo == hi) arr[lo] = min(arr[lo], lazy[rt]);
			else {
				int lc = rt << 1, rc = rt << 1 | 1;
				lazy[lc] = min(lazy[lc], lazy[rt]), lazy[rc] = min(lazy[rc], lazy[rt]);
			}
		}
		lazy[rt] = INFLL;
	}
 
	void insert(int y, ll c) {
		int rt = 1, lo = 0, hi = T - 1;
		while (true) {
			push(rt, lo, hi);
			++cnt[rt];
			if (lo == hi) {
				assert(valY[lo] == y);
				arr[lo] = min(arr[lo], c);
				break;
			}
			int md = (lo + hi) >> 1;
			(y <= valY[md]) ? (rt = rt << 1, hi = md) : (rt = rt << 1 | 1, lo = md + 1);
		}
	}
 
	void remove(int y) {
		int rt = 1, lo = 0, hi = T - 1;
		while (true) {
			push(rt, lo, hi);
			--cnt[rt];
			if (lo == hi) {
				if (cnt[rt] == 0) arr[lo] = INFLL;
				break;
			}
			int md = (lo + hi) >> 1;
			(y <= valY[md]) ? (rt = rt << 1, hi = md) : (rt = rt << 1 | 1, lo = md + 1);
		}
	}
 
	void minimize(int l, int r, ll c, int rt, int lo, int hi) {
		if (valY[hi] < l || r < valY[lo] || !cnt[rt] || lazy[rt] <= c) return;
		push(rt, lo, hi);
		if (l <= valY[lo] && valY[hi] <= r) return lazy[rt] = min(lazy[rt], c), void(0);
		int lc = rt << 1, rc = rt << 1 | 1, md = (lo + hi) >> 1;
		minimize(l, r, c, lc, lo, md), minimize(l, r, c, rc, md + 1, hi);
	}
	void minimize(int l, int r, ll c) { minimize(l, r, c, 1, 0, T - 1); }
 
	ll get(int l, int r, bool minY, int rt, int lo, int hi, bool &found) {
		if (valY[hi] < l || r < valY[lo] || !cnt[rt] || found) return INFLL;
		push(rt, lo, hi);
		if (lo == hi) return found = true, arr[lo];
		int lc = rt << 1, rc = rt << 1 | 1, md = (lo + hi) >> 1;
 
		ll ans = INFLL;
		if (minY) {
			ans = get(l, r, minY, lc, lo, md, found);
			if (!found) ans = get(l, r, minY, rc, md + 1, hi, found);
		} else {
			ans = get(l, r, minY, rc, md + 1, hi, found);
			if (!found) ans = get(l, r, minY, lc, lo, md, found);
		}
		return ans;
	}
	ll get(int l, int r, bool minY) { bool found = false; return get(l, r, minY, 1, 0, T - 1, found); }
};
 
vector<vector<pair<int, ll>>> solve(int start) {
	// cout << "solve " << start << endl;
	vector<vector<pair<int, ll>>> ans(M);
 
	vector<vector<int>> walksAdd(N), walksRem(N);
	vector<int> walkL(M, -1), walkR(M, -1);
	vector<int> walkIDs(M);
	iota(walkIDs.begin(), walkIDs.end(), 0);
	sort(walkIDs.begin(), walkIDs.end(), [&](int i, int j) { return Y[i] < Y[j]; });
	vector<int> lCols, rCols;
	for (int x = 0; x <= start; lCols.push_back(x++)) while (!lCols.empty() && H[lCols.back()] <= H[x]) lCols.pop_back();
	for (int x = N - 1; x >= start; rCols.push_back(x--)) while (!rCols.empty() && H[rCols.back()] <= H[x]) rCols.pop_back();
	for (int w : walkIDs) {
		if (L[w] <= start && start <= R[w] && Y[w] <= H[start]) { 
			walksAdd[walkL[w] = walkR[w] = start].push_back(w);
			walksRem[L[w]].push_back(w), walksRem[R[w]].push_back(w);
			continue; 
		}
 
		while (!lCols.empty() && H[lCols.back()] < Y[w]) lCols.pop_back();
		while (!rCols.empty() && H[rCols.back()] < Y[w]) rCols.pop_back();
		if (!rCols.empty() && rCols.back() <= L[w]) walksAdd[L[w]].push_back(w), walksRem[R[w]].push_back(w);
		else if (!lCols.empty() && lCols.back() >= R[w]) walksAdd[R[w]].push_back(w), walksRem[L[w]].push_back(w);
		else {
			if (!lCols.empty() && L[w] <= lCols.back()) walksAdd[walkL[w] = lCols.back()].push_back(w), walksRem[L[w]].push_back(w);
			if (!rCols.empty() && R[w] >= rCols.back()) walksAdd[walkR[w] = rCols.back()].push_back(w), walksRem[R[w]].push_back(w);
		}
	}
 
	// for (int x = 0; x < N; ++x) {
	// 	cout << x << ":\n";
	// 	for (auto w : walksRem[x]) cout << L[w] << ' ' << R[w] << ' ' << Y[w] << endl;
	// }
 
	vector<vector<SegmentTree>> st(2, vector<SegmentTree>(2, SegmentTree()));
	for (int w : walksAdd[start]) {
		if (L[w] < start) st[0][0].insert(Y[w], 0), st[0][1].insert(Y[w], Y[w]);
		if (R[w] > start) st[1][0].insert(Y[w], 0), st[1][1].insert(Y[w], Y[w]);
		ans[w].emplace_back(start, 0);
	}
 
	vector<vector<pair<int, ll>>> updates(N);
	int leftBorder = start, rightBorder = start;
	while (leftBorder > 0 || rightBorder < N - 1) {
		ll leftBest = st[0][0].get(0, H[leftBorder], false), rightBest = st[1][0].get(0, H[rightBorder], false);
		bool k = leftBest > rightBest;
		if (leftBorder == 0) k = 1;
		if (rightBorder == N - 1) k = 0;
 
		int col = (k == 0 ? --leftBorder : ++rightBorder);
 
		for (int w : walksAdd[col]) {
			ll curCost = min(st[k][0].get(0, Y[w], false), st[k][1].get(Y[w], H[col], true) - Y[w]);
			if (curCost == INFLL - Y[w]) curCost = INFLL;
			st[k][0].insert(Y[w], curCost), st[k][1].insert(Y[w], curCost + Y[w]);
			// cout << "pre dist " << col << ' ' << Y[w] << ": " << curCost << endl;
		}
 
		// cout << "S" << endl;
		for (auto upd : updates[col]) {
			// cout << "." << endl;
			int y = upd.first;
			ll c = upd.second;
			// cout << "upd " << y << ' ' << c << endl;
			st[k][0].minimize(y, H[col], c), st[k][1].minimize(0, y, c + y);
		}

		int prv = (k == 0 ? col + 1 : col - 1);
		if (H[prv] > H[col]) {
			ll curCost = st[k][1].get(H[col] + 1, H[prv], true);
			st[k][1].minimize(0, H[col], curCost);
		}

		// cout << "T" << endl;
		for (int w : walksAdd[col]) {
			ll curCost = min(st[k][0].get(Y[w], Y[w], false), st[k][1].get(Y[w], Y[w], false) - Y[w]);
			if (curCost == INFLL - Y[w]) curCost = INFLL;
			// cout << "dist " << col << ' ' << Y[w] << ": " << curCost << endl;
			ans[w].emplace_back(col, curCost);
 
			if (~walkL[w] && ~walkR[w] && walkL[w] <= start && start <= walkR[w]) {
				if (col == walkL[w]) updates[walkR[w]].emplace_back(Y[w], curCost + X[start] - X[col]);
				if (col == walkR[w]) updates[walkL[w]].emplace_back(Y[w], curCost + X[col] - X[start]);
			}
		}
 
		for (int w : walksRem[col]) {
			st[k][0].remove(Y[w]), st[k][1].remove(Y[w]);
		}
	}
 
	return ans;
}
 
ll min_distance(vector<int> x, vector<int> h, vector<int> l, vector<int> r, vector<int> y, int s, int t) {
	N = (int) x.size(), M = (int) y.size();
	X = x, H = h, L = l, R = r, Y = y;
	valY = Y;
	sort(valY.begin(), valY.end()), valY.erase(unique(valY.begin(), valY.end()), valY.end());
	T = (int) valY.size();
 
	vector<vector<pair<int, ll>>> ansS = solve(s);
	vector<vector<pair<int, ll>>> ansT = solve(t);
	ll ans = INFLL;
	for (int j = 0; j < M; ++j) {
		for (auto p : ansS[j]) for (auto q : ansT[j]) {
			ll cur = 0;
			cur += (ll) Y[j] * 2;
			cur += (ll) dist(p.first, q.first) + dist(p.first, s) + dist(q.first, t);
			cur += (p.second + q.second) * 2;
			// if (cur == 27) cout << L[j] << ' ' << R[j] << ' ' << Y[j] << " - " << p.first << ' ' << q.first << endl;
			ans = min(ans, cur);
		}
	}
 
	if (ans == INFLL) ans = -1;
	return ans;
}

Subtask #1
0 / 10.0

# Verdict Execution time Memory Grader output
1 Incorrect 0 ms 256 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #2
0 / 14.0

# Verdict Execution time Memory Grader output
1 Incorrect 0 ms 256 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #3
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 71 ms 9972 KB Output is correct
2 Correct 684 ms 69372 KB Output is correct
3 Correct 690 ms 70600 KB Output is correct
4 Correct 855 ms 79172 KB Output is correct
5 Correct 880 ms 77636 KB Output is correct
6 Correct 793 ms 79204 KB Output is correct
7 Correct 398 ms 44728 KB Output is correct
8 Correct 723 ms 81480 KB Output is correct
9 Correct 757 ms 80248 KB Output is correct
10 Correct 426 ms 51684 KB Output is correct
11 Correct 21 ms 5120 KB Output is correct

Subtask #4
0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 71 ms 9972 KB Output is correct
2 Correct 684 ms 69372 KB Output is correct
3 Correct 690 ms 70600 KB Output is correct
4 Correct 855 ms 79172 KB Output is correct
5 Correct 880 ms 77636 KB Output is correct
6 Correct 793 ms 79204 KB Output is correct
7 Correct 398 ms 44728 KB Output is correct
8 Correct 723 ms 81480 KB Output is correct
9 Correct 757 ms 80248 KB Output is correct
10 Correct 426 ms 51684 KB Output is correct
11 Correct 21 ms 5120 KB Output is correct
12 Correct 750 ms 70524 KB Output is correct
13 Correct 996 ms 79100 KB Output is correct
14 Correct 1045 ms 77432 KB Output is correct
15 Correct 622 ms 41840 KB Output is correct
16 Correct 660 ms 42036 KB Output is correct
17 Correct 637 ms 41924 KB Output is correct
18 Correct 605 ms 41912 KB Output is correct
19 Correct 603 ms 41928 KB Output is correct
20 Correct 507 ms 44156 KB Output is correct
21 Correct 162 ms 10496 KB Output is correct
22 Correct 664 ms 59716 KB Output is correct
23 Correct 600 ms 61016 KB Output is correct
24 Correct 676 ms 64892 KB Output is correct
25 Correct 643 ms 67116 KB Output is correct
26 Correct 666 ms 72464 KB Output is correct
27 Correct 940 ms 78216 KB Output is correct
28 Correct 996 ms 79212 KB Output is correct
29 Correct 1014 ms 79076 KB Output is correct
30 Correct 506 ms 44732 KB Output is correct
31 Correct 848 ms 80376 KB Output is correct
32 Correct 407 ms 37400 KB Output is correct
33 Incorrect 419 ms 38956 KB Output isn't correct
34 Halted 0 ms 0 KB -

Subtask #5
0 / 43.0

# Verdict Execution time Memory Grader output
1 Incorrect 0 ms 256 KB Output isn't correct
2 Halted 0 ms 0 KB -