oj.uz

Submission #258075

# Submission time Handle Problem Language Result Execution time Memory
258075 2020-08-05T10:02:31 Z atoiz Sky Walking (IOI19_walk) C++14
25 / 100
 4000 ms 81352 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]) 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) {
		if (valY[hi] < l || r < valY[lo] || !cnt[rt]) return INFLL;
		push(rt, lo, hi);
		if (lo == hi) return 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);
			if (ans == INFLL) ans = get(l, r, minY, rc, md + 1, hi);
		} else {
			ans = get(l, r, minY, rc, md + 1, hi);
			if (ans == INFLL) ans = get(l, r, minY, lc, lo, md);
		}
		return ans;
	}
	ll get(int l, int r, bool minY) { return get(l, r, minY, 1, 0, T - 1); }
};
 
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, MAXY, false), rightBest = st[1][0].get(0, MAXY, 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;
			st[k][0].minimize(y, MAXY, c), st[k][1].minimize(0, y, c + y);
		}
		// 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
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 256 KB Output is correct
2 Correct 0 ms 256 KB Output is correct
3 Correct 1 ms 256 KB Output is correct
4 Correct 0 ms 256 KB Output is correct
5 Correct 1 ms 384 KB Output is correct
6 Correct 1 ms 384 KB Output is correct
7 Correct 0 ms 384 KB Output is correct
8 Correct 1 ms 384 KB Output is correct
9 Correct 1 ms 256 KB Output is correct
10 Correct 1 ms 384 KB Output is correct
11 Correct 1 ms 384 KB Output is correct
12 Correct 1 ms 384 KB Output is correct
13 Correct 1 ms 384 KB Output is correct
14 Correct 1 ms 384 KB Output is correct
15 Correct 1 ms 256 KB Output is correct
16 Correct 0 ms 384 KB Output is correct
17 Correct 1 ms 384 KB Output is correct

Subtask #2
0 / 14.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 256 KB Output is correct
2 Correct 0 ms 256 KB Output is correct
3 Correct 655 ms 70588 KB Output is correct
4 Incorrect 827 ms 80324 KB Output isn't correct
5 Halted 0 ms 0 KB -

Subtask #3
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 75 ms 9972 KB Output is correct
2 Correct 651 ms 69408 KB Output is correct
3 Correct 715 ms 70728 KB Output is correct
4 Correct 893 ms 79072 KB Output is correct
5 Correct 767 ms 77544 KB Output is correct
6 Correct 891 ms 78892 KB Output is correct
7 Correct 421 ms 44964 KB Output is correct
8 Correct 804 ms 81352 KB Output is correct
9 Correct 751 ms 80252 KB Output is correct
10 Correct 465 ms 51556 KB Output is correct
11 Correct 22 ms 5120 KB Output is correct

Subtask #4
0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 75 ms 9972 KB Output is correct
2 Correct 651 ms 69408 KB Output is correct
3 Correct 715 ms 70728 KB Output is correct
4 Correct 893 ms 79072 KB Output is correct
5 Correct 767 ms 77544 KB Output is correct
6 Correct 891 ms 78892 KB Output is correct
7 Correct 421 ms 44964 KB Output is correct
8 Correct 804 ms 81352 KB Output is correct
9 Correct 751 ms 80252 KB Output is correct
10 Correct 465 ms 51556 KB Output is correct
11 Correct 22 ms 5120 KB Output is correct
12 Correct 662 ms 70496 KB Output is correct
13 Execution timed out 4069 ms 73592 KB Time limit exceeded
14 Halted 0 ms 0 KB -

Subtask #5
0 / 43.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 256 KB Output is correct
2 Correct 0 ms 256 KB Output is correct
3 Correct 1 ms 256 KB Output is correct
4 Correct 0 ms 256 KB Output is correct
5 Correct 1 ms 384 KB Output is correct
6 Correct 1 ms 384 KB Output is correct
7 Correct 0 ms 384 KB Output is correct
8 Correct 1 ms 384 KB Output is correct
9 Correct 1 ms 256 KB Output is correct
10 Correct 1 ms 384 KB Output is correct
11 Correct 1 ms 384 KB Output is correct
12 Correct 1 ms 384 KB Output is correct
13 Correct 1 ms 384 KB Output is correct
14 Correct 1 ms 384 KB Output is correct
15 Correct 1 ms 256 KB Output is correct
16 Correct 0 ms 384 KB Output is correct
17 Correct 1 ms 384 KB Output is correct
18 Correct 1 ms 256 KB Output is correct
19 Correct 0 ms 256 KB Output is correct
20 Correct 655 ms 70588 KB Output is correct
21 Incorrect 827 ms 80324 KB Output isn't correct
22 Halted 0 ms 0 KB -