Submission #400946

# Submission time Handle Problem Language Result Execution time Memory
400946 2021-05-08T21:43:22 Z 534351 From Hacks to Snitches (BOI21_watchmen) C++17
0 / 100
1329 ms 11332 KB
#include <bits/stdc++.h>

using namespace std;

template<class T, class U>
void ckmin(T &a, U b)
{
    if (a > b) a = b;
}

template<class T, class U>
void ckmax(T &a, U b)
{
    if (a < b) a = b;
}

#define MP make_pair
#define PB push_back
#define LB lower_bound
#define UB upper_bound
#define fi first
#define se second
#define SZ(x) ((int) (x).size())
#define ALL(x) (x).begin(), (x).end()
#define FOR(i, a, b) for (auto i = (a); i < (b); i++)
#define FORD(i, a, b) for (auto i = (a) - 1; i >= (b); i--)

const int MAXN = 250013;
const int INF = 1e9 + 7;
const int DELTA = 44;

typedef long long ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef vector<int> vi;
typedef vector<ll> vl;
typedef vector<pii> vpi;
typedef vector<pll> vpl;

int N, M, K;
vi edge[MAXN];
pii ban[MAXN];
int dist[MAXN], cc[MAXN];
bitset<DELTA + 3> seen[MAXN];
priority_queue<pii, vector<pii>, greater<pii> > pq;

int32_t main()
{
    cout << fixed << setprecision(12);
    cerr << fixed << setprecision(4);
    ios_base::sync_with_stdio(false); cin.tie(0);
    cin >> N >> M;
    FOR(i, 0, M)
    {
        int u, v;
        cin >> u >> v; u--; v--;
        edge[u].PB(v);
        edge[v].PB(u);
    }
    FOR(i, 0, N)
    {
        edge[i].PB(i);
        cc[i] = -1;
    }
    cin >> K;
    FOR(i, 0, K)
    {
        int c; cin >> c;
        vi s(c);
        FOR(j, 0, c)
        {
            cin >> s[j]; s[j]--;
            ban[s[j]] = {j, c};
            cc[s[j]] = i;
        }
    }
    fill(dist, dist + N, INF);
    dist[0] = 0;
    pq.push({0, 0});
    while(!pq.empty())
    {
        int d = pq.top().fi, u = pq.top().se; pq.pop();
        if (d - dist[u] >= DELTA) continue;
        // cerr << d << ' ' << u << endl;
        if (seen[u][d - dist[u]]) continue;
        seen[u][d - dist[u]] = true;
        for (int v : edge[u])
        {
            if (cc[v] != -1)
            {
                // cerr << "check " << d + 1 << ' ' << v << endl;
                int m = ban[v].se;
                if ((d + 1) % ban[v].se == ban[v].fi) continue;
                if (cc[u] == cc[v] && (d + 1) % m == ban[u].fi && d % m == ban[v].fi) continue;
            }
            if (dist[v] > d + 1)
            {
                dist[v] = d + 1;
            }
            // cerr << u << ' ' << v << ' ' << d + 1 << endl;
            pq.push({d + 1, v});
            //you can go from u -> v at time t iff:
            //t != ban[v].fi mod ban[v].se
            //t-1 != ban[u][v].fi mod ban[u][v].se
        }
    }
    if (dist[N - 1] >= INF)
    {
        cout << "impossible\n";
        return 0;
    }
    cout << dist[N - 1] << '\n';
    return 0;
}
# Verdict Execution time Memory Grader output
1 Correct 1116 ms 9248 KB Output is correct
2 Incorrect 1319 ms 11248 KB Output isn't correct
3 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 1140 ms 9300 KB Output is correct
2 Incorrect 1329 ms 11332 KB Output isn't correct
3 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 1140 ms 9300 KB Output is correct
2 Incorrect 1329 ms 11332 KB Output isn't correct
3 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 1140 ms 9300 KB Output is correct
2 Incorrect 1329 ms 11332 KB Output isn't correct
3 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 1116 ms 9248 KB Output is correct
2 Incorrect 1319 ms 11248 KB Output isn't correct
3 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 1116 ms 9248 KB Output is correct
2 Incorrect 1319 ms 11248 KB Output isn't correct
3 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 1116 ms 9248 KB Output is correct
2 Incorrect 1319 ms 11248 KB Output isn't correct
3 Halted 0 ms 0 KB -