Submission #32889

#	Time	Username	Problem	Language	Result	Execution time	Memory
32889		minimario	Jakarta Skyscrapers (APIO15_skyscraper)	C++14	22 / 100	53 ms	147988 KiB

skyscraper

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

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

#define f first
#define s second

const int MAX = 30005;
const int SQRT = 175;
const int INF = 1000000000;
int p[MAX], len[MAX]; // position, length

vector<pair<pii, int> > g[MAX][SQRT];
vector<int> powers[MAX]; // powers of doges at a given position

int dist[MAX][SQRT];

priority_queue<pair<int, pair<int, int> > > pq;
int ct = 0;
void dijk(int i, int j) {
	dist[i][j] = 0;
	//cout << i << " " << j << " " << 0 << endl;
	pq.push({0, {i, j}});
	while (!pq.empty()) {
		auto top = pq.top(); pq.pop();
		ct++;
		int d = -top.f;
		pair<int, int> loc = top.s;
		if (d > dist[loc.f][loc.s]) {
			continue; 
		}
		for (auto i : g[loc.f][loc.s]) {
			int d_new = (d + i.s);
			if (d_new < dist[i.f.f][i.f.s]) {
				dist[i.f.f][i.f.s] = d_new;
				//cout << i.f.f << " " << i.f.s << " " << d_new << endl;

				pq.push({-d_new, i.f});

			}
		}

	}
}
int main() {
	//freopen("a.in", "r", stdin);
	//freopen("a.out", "w", stdout);

	for (int i=0; i<MAX; i++) {
		for (int j=0; j<SQRT; j++) {
			dist[i][j] = INF; 
		}
	}

	int n, m; scanf("%d %d", &n, &m);
	for (int i=0; i<m; i++) {
		scanf("%d %d", &p[i], &len[i]);
		powers[p[i]].push_back(len[i]);
	}

	for (int i=0; i<n; i++) {
		for (int j=1; j<SQRT; j++) {
			g[i][j].push_back({{i, 0}, 0});
		}
		for (int j : powers[i]) {
			g[i][0].push_back({{i, j}, 0});
		}
	}
	for (int i=0; i<m; i++) {
		if (len[i] > SQRT) {
			for (int j=i+len[i]; j<n; j+=len[i]) {
				g[i][0].push_back({{j, 0}, (j-i)/len[i]});
			}
			for (int j=i-len[i]; j>=0; j-=len[i]) {
				g[i][0].push_back({{j, 0}, (i-j)/len[i]});
			}
		}
	}
	// 0 36
	// 36 63
	for (int i=0; i<n; i++) {
		for (int j=1; j<SQRT; j++) {
			if (i-j >= 0) { g[i][j].push_back({{i-j, j}, 1}); }
			if (i+j < n) { g[i][j].push_back({{i+j, j}, 1}); }
		}
		/*
		if (p[i] - len[i] >= 0) {
			g[p[i]][len[i]].push_back({{p[i]-len[i], len[i]}, 1});
		}
		if (p[i] + len[i] < n) {
			g[p[i]][len[i]].push_back({{p[i]+len[i], len[i]}, 1});
		}
		*/
	}
	dijk(p[0], len[0]);
	if (dist[p[1]][len[1]] == INF) { printf("%d\n", -1); }
	else { printf("%d\n", dist[p[1]][len[1]]); }
}

Compilation message (stderr)

skyscraper.cpp: In function 'int main()':
skyscraper.cpp:57:34: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  int n, m; scanf("%d %d", &n, &m);
                                  ^
skyscraper.cpp:59:33: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d %d", &p[i], &len[i]);
                                 ^

• Subtask 1: 10 / 10
• Subtask 2: 12 / 12
• Subtask 3: 0 / 14
• Subtask 4: 0 / 21
• Subtask 5: 0 / 43