Submission #1279488

#	Time	Username	Problem	Language	Result	Execution time	Memory
1279488		mactoddlover	Bitaro’s Party (JOI18_bitaro)	C++17	0 / 100	5 ms	9792 KiB

bitaro

#include<bits/stdc++.h>

#define MASK(i) (1 << (i))
#define pub push_back
#define all(v) v.begin(), v.end()
#define compact(v) v.erase(unique(all(v)), end(v))
#define pii pair<int,int>
#define fi first
#define se second
#define endl "\n"
#define sz(v) (int)(v).size()
#define dbg(x) "[" #x " = " << (x) << "]"
#define vi vector<int>

using namespace std;

template<class T> bool minimize(T& a, T b){if(a > b) return a = b, true;return false;}
template<class T> bool maximize(T& a, T b){if(a < b) return a = b, true;return false;}

typedef long long ll;
typedef long double ld;

mt19937_64 rng(chrono::high_resolution_clock::now().time_since_epoch().count());
ll rand(ll l, ll r){return uniform_int_distribution<ll>(l, r)(rng);}

const int MAX = 2e5 + 15;
const int block_sz = 550;

int n, m, q;
vector<int> g[MAX];
vector<pii> dp[MAX];
bool busy[MAX];
int f[MAX];

void solve(){
    cin >> n >> m >> q;

    for(int i = 1; i <= m; i++){
        int u, v; cin >> u >> v;
        g[v].push_back(u); //reverse edge
    }

    for(int u = 1; u <= n; u++){
        map<int, int> mp;
        for(int v : g[u]){
            for(auto &[k, node] : dp[v]) maximize(mp[node], k+1);
        }
        for(auto e : mp) dp[u].push_back({e.se, e.fi});
        sort(all(dp[u]), greater<pii>());
        while(sz(dp[u]) > block_sz) dp[u].pop_back();
        dp[u].push_back({0, u});
    }

    while(q--){
        int u, num; cin >> u >> num;
        vector<int> ban;
        while(num--){
            int x; cin >> x;
            ban.push_back(x);
            busy[x] = true;
        }

        if(sz(ban) < block_sz){
            for(auto &[k, node] : dp[u]){
                if(!busy[node]){
                    cout << k << endl;
                    break;
                }
            }
        }
        else{
            fill(f + 1, f + 1 + n, 0);
            for(int i = 1; i <= u; i++){
                for(int j : g[i]) if(!busy[j] || f[j]){
                    maximize(f[i], f[j] + 1);
                }
            }
            cout << f[u] << endl;
        }

        for(int x : ban) busy[x] = false;
    }
}

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

    #define task "task"

    if(fopen(task".INP", "r")){
        freopen(task".INP", "r", stdin);
        freopen(task".OUT", "w", stdout);
    }

    int t; t = 1; //cin >> t;
    while(t--) solve();
}

Compilation message (stderr)

bitaro.cpp: In function 'int main()':
bitaro.cpp:92:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   92 |         freopen(task".INP", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
bitaro.cpp:93:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   93 |         freopen(task".OUT", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

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