oj.uz

Submission #210488

# Submission time Handle Problem Language Result Execution time Memory
210488 2020-03-17T14:08:54 Z hanagasumi Railway Trip (JOI17_railway_trip) C++17
20 / 100
 2000 ms 13432 KB 
#include <iostream>
#include <vector>
#include <cmath>
#include <algorithm>
#include <deque>
#include <map>
#include <set>
#include <complex>
#include <string>
#include <unordered_map>
#include <unordered_set>
#include <random>
#include <chrono>

#define ft first
#define sc second
#define pb push_back
#define len(v) (int)v.size()
#define int ll

using namespace std;
typedef long long ll;
typedef long double ld;

int inf = 1e9 + 100;

signed main() {
	#ifdef PC
		freopen("in.txt", "r", stdin);
		freopen("out.txt", "w", stdout);
	#endif	
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);

	int n, k, q;
	cin >> n >> k >> q;
	vector<int> l(n);
	vector<vector<int>> g(n);
	for (int i = 0; i < n; i++) {
		cin >> l[i];
	}

	vector<int> pred(n, -1);
	vector<int> nxt(n, n);
	vector<pair<int, int>> have;
	for (int i = 0; i < n; i++) {
		while(len(have) > 0 && have.back().ft <= l[i]) 
			have.pop_back();
		if(len(have) > 0) 
			pred[i] = have.back().sc;
		have.pb({l[i], i});
	}
	have.clear();
	for (int i = n - 1; i >= 0; i--) {
		while(len(have) > 0 && have.back().ft <= l[i]) 
			have.pop_back();
		if(len(have) > 0)
			nxt[i] = have.back().sc;
		have.pb({l[i], i});
	}

	for (int i = 0; i < n; i++) {
		if(i < n - 1) 
			g[i].pb(i + 1);
		int now = i - 1;
		while(1) {
			if(now < 0) 
				break;
			g[i].pb(now);
			if(l[now] >= l[i]) 
				break;
			now = pred[now];
		}
		now = i + 1;
		while(1) {
			if(now >= n) 
				break;
			g[i].pb(now);
			if(l[now] >= l[i]) 
				break;
			now = nxt[now];
		}
	}

	for (int i = 0; i < q; i++) {		
		int a, b;
		cin >> a >> b;
		a--, b--;

		vector<int> dst(n, inf);
		dst[a] = 0;
		deque<int> q;
		q.pb(a);
		while(len(q) > 0) {
			auto now = q.front();
			q.pop_front();
			for (auto x : g[now]) {
				if(dst[x] != inf) 
					continue;
				dst[x] = dst[now] + 1;
				q.pb(x);
			}
		}
		cout << dst[b] - 1 << '\n';
	}

	return 0;
}

Subtask #1
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 5 ms 376 KB Output is correct
2 Correct 5 ms 376 KB Output is correct
3 Correct 5 ms 376 KB Output is correct
4 Correct 5 ms 376 KB Output is correct
5 Correct 5 ms 376 KB Output is correct
6 Correct 5 ms 376 KB Output is correct
7 Correct 6 ms 376 KB Output is correct
8 Correct 5 ms 376 KB Output is correct
9 Correct 4 ms 380 KB Output is correct

Subtask #2
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 7 ms 504 KB Output is correct
2 Correct 225 ms 12024 KB Output is correct
3 Correct 260 ms 12516 KB Output is correct
4 Correct 278 ms 12664 KB Output is correct
5 Correct 288 ms 12664 KB Output is correct
6 Correct 285 ms 12920 KB Output is correct
7 Correct 330 ms 13304 KB Output is correct
8 Correct 98 ms 10744 KB Output is correct
9 Correct 104 ms 12404 KB Output is correct
10 Correct 99 ms 11772 KB Output is correct
11 Correct 195 ms 11896 KB Output is correct
12 Correct 207 ms 12024 KB Output is correct
13 Correct 196 ms 11896 KB Output is correct
14 Correct 204 ms 11896 KB Output is correct
15 Correct 211 ms 11896 KB Output is correct
16 Correct 212 ms 11896 KB Output is correct
17 Correct 375 ms 13400 KB Output is correct
18 Correct 368 ms 13304 KB Output is correct
19 Correct 213 ms 12816 KB Output is correct

Subtask #3
0 / 25.0

# Verdict Execution time Memory Grader output
1 Execution timed out 2089 ms 12404 KB Time limit exceeded
2 Halted 0 ms 0 KB -

Subtask #4
0 / 55.0

# Verdict Execution time Memory Grader output
1 Execution timed out 2094 ms 13432 KB Time limit exceeded
2 Halted 0 ms 0 KB -