Submission #530876

#	Time	Username	Problem	Language	Result	Execution time	Memory
530876		KazamaHoang	Bitaro’s Party (JOI18_bitaro)	C++14	100 / 100	1096 ms	287804 KiB

bitaro

// no matter how hard you work, someone else is working harder
#include <bits/stdc++.h>
#define FOR(i, a, b) for (int i = (a), _i = (b); i <= _i; ++ i)
#define FORD(i, b, a) for (int i = (b), _i = (a); i >= _i; -- i)
#define REP(i, b) for (int i = 0, _i = (b); i < _i; ++ i)
#define FORE(i, a) for (auto& i : a)
#define lb lower_bound
#define ub upper_bound
#define pb push_back
#define mp make_pair
#define F first
#define S second
#define cntbit __builtin_popcountll
#define len(x) (int)x.size()
#define bit(x, i) (((x) >> (i)) & 1)
#define all(x) x.begin(), x.end()
using namespace std;
using ll = long long;
template <typename A, typename B>
inline bool ckmax(A& a, const B& b) {
    if (a < b) {
        a = b;
        return true;
    } return false;
}
template <typename A, typename B>
inline bool ckmin(A& a, const B& b) {
    if (a > b) {
        a = b;
        return true;
    } return false;
}
inline void fileIO(const string& Task = "") {
    ios::sync_with_stdio(false); cin.tie(NULL);
    if (fopen((Task + ".inp").c_str(), "r")) {
        freopen((Task + ".inp").c_str(), "r", stdin);
        freopen((Task + ".out").c_str(), "w", stdout);
    }
}

/* Author: Hoang Quoc Viet */

/** END OF TEMPLATE **/

const int B = 350;

int n, m, q;
vector<int> revAdj[100005];
vector<pair<int, int>> far_from[100005];
int timer = 0, used[100005];

int main() {
    fileIO("main");

    cin >> n >> m >> q;
    FOR(i, 1, m) {
        int u, v;
        cin >> u >> v;
        revAdj[v].pb(u);
    }

    FOR(u, 1, n) {
        far_from[u].pb(mp(0, u));
        FORE(v, revAdj[u]) {
            vector<pair<int, int>> tmp = far_from[v], cur = far_from[u], res;
            FORE(cc, tmp) ++ cc.F;
            int run_tmp = 0, run_cur = 0;
            ++ timer;
            while (run_tmp < len(tmp) && run_cur < len(cur) && len(res) < B) {
                if (tmp[run_tmp].F >= cur[run_cur].F) {
                    if (used[tmp[run_tmp].S] != timer) {
                        used[tmp[run_tmp].S] = timer;
                        res.pb(tmp[run_tmp]);
                    }
                    ++ run_tmp;
                } else {
                    if (used[cur[run_cur].S] != timer) {
                        used[cur[run_cur].S] = timer;
                        res.pb(cur[run_cur]);
                    }
                    ++ run_cur;
                }
            }
            while (run_tmp < len(tmp) && len(res) < B) {
                if (used[tmp[run_tmp].S] != timer) {
                    used[tmp[run_tmp].S] = timer;
                    res.pb(tmp[run_tmp]);
                }
                ++ run_tmp;
            }
            while (run_cur < len(cur) && len(res) < B) {
                if (used[cur[run_cur].S] != timer) {
                    used[cur[run_cur].S] = timer;
                    res.pb(cur[run_cur]);
                }
                ++ run_cur;
            }
            far_from[u] = res;
        }
    }

    while (q --) {
        int u, y;
        cin >> u >> y;
        ++ timer;
        FOR(i, 1, y) {
            int x;
            cin >> x;
            used[x] = timer;
        }
        if (y >= B) {
            vector<int> dp(n+5, -1);
            for (int i = 1; i <= u; ++ i) {
                if (used[i] != timer) dp[i] = 0;
                FORE(j, revAdj[i]) if (dp[j] != -1) {
                    ckmax(dp[i], dp[j] + 1);
                }
            }
            cout << dp[u] << "\n";
        } else {
            int res = -1;
            FORE(p, far_from[u]) if (used[p.S] != timer) {
                ckmax(res, p.F);
            }
            cout << res << "\n";
        }
    }

    return 0;
}

/*** VOI VOI VOI important things must be said three times :> ***/

Compilation message (stderr)

bitaro.cpp: In function 'void fileIO(const string&)':
bitaro.cpp:36:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   36 |         freopen((Task + ".inp").c_str(), "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
bitaro.cpp:37:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   37 |         freopen((Task + ".out").c_str(), "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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