Submission #1142338

#	Time	Username	Problem	Language	Result	Execution time	Memory
1142338		hoa208	Bitaro’s Party (JOI18_bitaro)	C++20	14 / 100	1262 ms	212788 KiB

bitaro

#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define FOR(i, a, b) for (int i = (a), _b = (b); i <= _b; i++)
#define FORD(i, b, a) for (int i = (b), _a = (a); i >= _a; i--)
#define pa pair<ll, ll>
#define fi first
#define se second
#define bit(mask, j) ((mask >> j) & 1)
#define t_test int t;cin >> t;while(t--)
const ll mod = 1e9 + 7;
const ll INF = 1e17;
const ll B = 100;
const ll N = 1e5 + 5;
ll n, m, q;
ll a[N], dx[N], dp[N];
vector<ll> r_g[N];
vector<pa> dist[N];
void slove2(ll &t, ll &y) {
    FORD(i, t, 1) {
        dp[i] = -1;
    }
    dp[t] = 0;
    FORD(i, t, 1) {
        if(dp[i] == -1) continue;
        for(auto v : r_g[i]) {
            dp[v] = max(dp[i] + 1, dp[v]);
        }
    }
    ll ans = -1;
    FOR(i, 1, t) {
        if(!dx[i]) {
            ans = max(ans, dp[i]);
        }
    }
    cout << ans << '\n';
    FOR(i, 1, y) {
        dx[a[i]] = 0;
    }
}
void hbmt() {
    // inp
    cin >> n >> m >> q;
    FOR(i, 1, m) {
        ll u, v;
        cin >> u >> v;
        r_g[v].push_back(u);
    }
    // pre
    FOR(i, 1, n) {
        vector<pa> vt;
        for(auto v : r_g[i]) {
            for(auto e : dist[v]) {
                vt.push_back({e.fi + 1, e.se});
            }
            vt.push_back({1, v});
        }
        vt.push_back({0, i});
        sort(vt.begin(), vt.end(), greater<pa>());
        vt.erase(unique(vt.begin(), vt.end()), vt.end());
        while(vt.size() > B) {
            vt.pop_back();
        }
        for(auto v : vt) {
            dist[i].push_back(v);
        }
    }
    ll t, y;
    FOR(i, 1, q) {
        cin >> t >> y;
        FOR(j, 1, y) {
            cin >> a[j];
            dx[a[j]] = 1;
        }
        if(y >= B) {
            slove2(t, y);
            continue;
        }
        bool ok = false;
        for(auto e : dist[t]) {
            if(dx[e.se] == 0) {
                ok = true;
                cout << e.fi << '\n';
                break;
            }
        }
        if(!ok) cout << -1 << '\n';
        FOR(j, 1, y) {
            dx[a[j]] = 0;
        }
    }
}

int main() {
    
    ios_base::sync_with_stdio(0);
    cin.tie(0);cout.tie(0);

    if(fopen("hbmt.inp", "r")) {
        freopen("hbmt.inp", "r", stdin);
        freopen("hbmt.out", "w", stdout);
    }
    
    // t_test 
    hbmt();
    return 0;
}

Compilation message (stderr)

bitaro.cpp: In function 'int main()':
bitaro.cpp:100:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  100 |         freopen("hbmt.inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
bitaro.cpp:101:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  101 |         freopen("hbmt.out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 7 / 7
• Subtask 2: 7 / 7
• Subtask 3: 0 / 86