oj.uz

Submission #93605

# Submission time Handle Problem Language Result Execution time Memory
93605 2019-01-10T02:20:27 Z silxikys Bitaro’s Party (JOI18_bitaro) C++14
7 / 100
 426 ms 59640 KB 
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;

const int maxn = 1e5+5, INF = 987654321;
int N, M, Q;
vector<int> ancestors[maxn];
int SZ;
list<pair<int,int>> bests[maxn];
auto cmp = [](const pair<int,int>& a, const pair<int,int>& b) { return a.first > b.first; };

bool used[maxn], isBusy[maxn];
int main()
{
    ios_base::sync_with_stdio(false); cin.tie(NULL);
    cin >> N >> M >> Q;
    for (int i = 0; i < M; i++) {
    	int s, e; cin >> s >> e;
    	ancestors[e].push_back(s);
    }
    SZ = 20; //each node will store at least the top SZ nodes
    //small queries are <= SZ - 1
    for (int i = 1; i <= N; i++) {
    	list<pair<int,int>>& li = bests[i];
    	li.push_back({0,i});
    	for (int j: ancestors[i]) {
    		list<pair<int,int>> add;
    		for (auto p: bests[j]) {
    			add.push_back({p.first+1,p.second});
    			if ((int)add.size() >= SZ) break;
    		}
    		li.merge(add,cmp);
    		li.unique();
    		for (auto it = li.begin(); it != li.end();) {
	    		if (used[it->second]) it = li.erase(it);
	    		else { used[it->second] = true;	++it; }
	    	}
	    	for (auto& p: li) used[p.second] = false; //reset for next one
	    	while ((int)li.size() > SZ) li.pop_back();
    	}
    	
    	
    	/*
    	cout << i << ": \n";
    	for (auto p: li) {
    		cout << p.first << ' ' << p.second << '\n';
    	}
    	cout << '\n';
    	*/
    }

    if (N > 1000) return 0;

	while (Q--) {
		int town, num; cin >> town >> num;
		vector<int> busy(num);
		for (int i = 0; i < num; i++) {
			cin >> busy[i];
			isBusy[busy[i]] = true;
		}
		if (num <= SZ - 1) {
			//answer will be in first SZ answers, if it exists
			bool found = false;
			for (auto& p: bests[town]) {
				if (!isBusy[p.second]) {
					found = true;
					cout << p.first << '\n';
					break;
				}
			}
			if (!found) {
				cout << -1 << '\n';
			}
		}
		else {
			//do normal O(N) DP
			//this only happens about sqrt(N) times
			vector<int> dp(N+1,-INF);
			for (int i = 1; i <= town; i++) {
				if (!isBusy[i]) dp[i] = 0;
				for (int j: ancestors[i]) {
					dp[i] = max(dp[i],dp[j]+1);
				}
			}
			int ans = dp[town] >= 0 ? dp[town] : -1;
			cout << ans << '\n';
		}
		//reset isBusy[] for next query
		for (int i: busy) isBusy[i] = false;
	}
    return 0;
}

Subtask #1
7.0 / 7.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 4984 KB Output is correct
2 Correct 6 ms 4984 KB Output is correct
3 Correct 6 ms 4988 KB Output is correct
4 Correct 6 ms 5112 KB Output is correct
5 Correct 7 ms 5496 KB Output is correct
6 Correct 8 ms 5632 KB Output is correct
7 Correct 9 ms 5624 KB Output is correct
8 Correct 8 ms 5752 KB Output is correct
9 Correct 7 ms 5752 KB Output is correct
10 Correct 9 ms 5752 KB Output is correct
11 Correct 9 ms 5752 KB Output is correct
12 Correct 9 ms 5624 KB Output is correct
13 Correct 9 ms 5624 KB Output is correct
14 Correct 9 ms 5496 KB Output is correct
15 Correct 8 ms 5496 KB Output is correct
16 Correct 8 ms 5496 KB Output is correct
17 Correct 9 ms 5624 KB Output is correct
18 Correct 8 ms 5496 KB Output is correct
19 Correct 9 ms 5624 KB Output is correct

Subtask #2
0 / 7.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 4984 KB Output is correct
2 Correct 6 ms 4984 KB Output is correct
3 Correct 6 ms 4988 KB Output is correct
4 Correct 6 ms 5112 KB Output is correct
5 Correct 7 ms 5496 KB Output is correct
6 Correct 8 ms 5632 KB Output is correct
7 Correct 9 ms 5624 KB Output is correct
8 Correct 8 ms 5752 KB Output is correct
9 Correct 7 ms 5752 KB Output is correct
10 Correct 9 ms 5752 KB Output is correct
11 Correct 9 ms 5752 KB Output is correct
12 Correct 9 ms 5624 KB Output is correct
13 Correct 9 ms 5624 KB Output is correct
14 Correct 9 ms 5496 KB Output is correct
15 Correct 8 ms 5496 KB Output is correct
16 Correct 8 ms 5496 KB Output is correct
17 Correct 9 ms 5624 KB Output is correct
18 Correct 8 ms 5496 KB Output is correct
19 Correct 9 ms 5624 KB Output is correct
20 Correct 200 ms 6828 KB Output is correct
21 Correct 196 ms 6840 KB Output is correct
22 Correct 202 ms 6872 KB Output is correct
23 Correct 197 ms 7024 KB Output is correct
24 Incorrect 426 ms 59640 KB Output isn't correct
25 Halted 0 ms 0 KB -

Subtask #3
0 / 86.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 4984 KB Output is correct
2 Correct 6 ms 4984 KB Output is correct
3 Correct 6 ms 4988 KB Output is correct
4 Correct 6 ms 5112 KB Output is correct
5 Correct 7 ms 5496 KB Output is correct
6 Correct 8 ms 5632 KB Output is correct
7 Correct 9 ms 5624 KB Output is correct
8 Correct 8 ms 5752 KB Output is correct
9 Correct 7 ms 5752 KB Output is correct
10 Correct 9 ms 5752 KB Output is correct
11 Correct 9 ms 5752 KB Output is correct
12 Correct 9 ms 5624 KB Output is correct
13 Correct 9 ms 5624 KB Output is correct
14 Correct 9 ms 5496 KB Output is correct
15 Correct 8 ms 5496 KB Output is correct
16 Correct 8 ms 5496 KB Output is correct
17 Correct 9 ms 5624 KB Output is correct
18 Correct 8 ms 5496 KB Output is correct
19 Correct 9 ms 5624 KB Output is correct
20 Correct 200 ms 6828 KB Output is correct
21 Correct 196 ms 6840 KB Output is correct
22 Correct 202 ms 6872 KB Output is correct
23 Correct 197 ms 7024 KB Output is correct
24 Incorrect 426 ms 59640 KB Output isn't correct
25 Halted 0 ms 0 KB -