Submission #87780

#	Time	Username	Problem	Language	Result	Execution time	Memory
87780		KCSC	Jakarta Skyscrapers (APIO15_skyscraper)	C++14	100 / 100	625 ms	123452 KiB

skyscraper

#include <bits/stdc++.h>
using namespace std;

const int DIM = 30005;

int ans[DIM]; 
pair<int, int> arr[DIM];
vector<int> lst[DIM];
bitset<DIM> oki[DIM], vis;

struct str {
	int ps, pw, tm; };
deque<str> que;

int main(void) {
#ifdef HOME
	freopen("skyscraper.in", "r", stdin); 
	freopen("skyscraper.out", "w", stdout);
#endif
	int n, m; cin >> n >> m;
	for (int i = 0; i < m; ++i) {
		cin >> arr[i].first >> arr[i].second;
		lst[arr[i].first].push_back(i); ans[i] = 1000000000; }
	que.push_back({arr[0].first, arr[0].second, 0}); 
	ans[0] = 0; oki[arr[0].first][arr[0].second] = true;
	while (que.size()) {
		int ps = que.front().ps, pw = que.front().pw, tm = que.front().tm; 
		que.pop_front();
		if (!vis[ps]) {
			vis[ps] = true;
			for (int x : lst[ps]) {
				ans[x] = min(ans[x], tm);
				if (!oki[arr[x].first][arr[x].second]) {		
					oki[arr[x].first][arr[x].second] = true; 
					que.push_front({arr[x].first, arr[x].second, tm}); } } }
		if (ps + pw < n and !oki[ps + pw][pw]) {
			oki[ps + pw][pw] = true; 
			que.push_back({ps + pw, pw, tm + 1}); }
		if (ps - pw >= 0 and !oki[ps - pw][pw]) {
			oki[ps - pw][pw] = true; 
			que.push_back({ps - pw, pw, tm + 1}); } }
	if (ans[1] == 1000000000) {
		ans[1] = -1; }
	cout << ans[1];		 
	return 0; }	

• Subtask 1: 10 / 10
• Subtask 2: 12 / 12
• Subtask 3: 14 / 14
• Subtask 4: 21 / 21
• Subtask 5: 43 / 43