Submission #563481

#	Time	Username	Problem	Language	Result	Execution time	Memory
563481		Soul234	Regions (IOI09_regions)	C++14	100 / 100	3880 ms	31932 KiB

regions

#include<bits/stdc++.h>
using namespace std;

void DBG() { cerr << "]\n"; }
template<class H, class... T> void DBG(H h, T... t) {
    cerr << h; if(sizeof...(t)) cerr << ", ";
    DBG(t...);
}
#ifdef LOCAL
#define dbg(...) cerr << "[" << #__VA_ARGS__ << "]: [", DBG(__VA_ARGS__)
#else
#define dbg(...) 0
#endif // LOCAL

#define FOR(i,a,b) for(int i = (a) ; i<(b) ; i++)
#define F0R(i,a) FOR(i,0,a)
#define ROF(i,a,b) for(int i = (b)-1 ; i>=(a) ; i--)
#define R0F(i,a) ROF(i,0,a)
#define each(e,a) for(auto &e : (a))
#define sz(v) (int)(v).size()
#define all(v) (v).begin(),(v).end()
#define rall(v) (v).rbegin(),(v).rend()
#define pb push_back
#define tcT template<class T
#define nl "\n"

using ll = long long;
using vi = vector<int>;
using pi = pair<int,int>;
using str = string;
tcT> using V = vector<T>;
tcT> using pqg = priority_queue<T,vector<T>,greater<T>>;

void setIO(string NAME = "") {
    cin.tie(0)->sync_with_stdio(0);
    if(sz(NAME)) {
        freopen((NAME + ".inp").c_str(),"r",stdin);
        freopen((NAME + ".out").c_str(),"w",stdout);
    }
}

const int BL = 447;
const int MX = 2e5+5, MXR = 25005;
int N, R, Q, typ[MX], _timer, IDs[MX], IDtour[MX], tin[MX], tout[MX];
ll preans[BL][MXR];
vi adj[MX], reg[MXR];

void Flat(int u, int p) {
    IDtour[tin[u] = ++_timer] = u;
    reg[typ[u]].pb(tin[u]);
    each(v, adj[u]) if(v!=p) Flat(v, u);
    tout[u] = _timer;
}

void dfs(int u, int p, int idx, int cnt) {
    if(typ[u] == idx) cnt++;
    else preans[IDs[idx]][typ[u]] += cnt;
    each(v, adj[u]) if(v != p) dfs(v, u, idx, cnt);
}

void solve() {
    cin>>N>>R>>Q;
    cin>>typ[1];
    FOR(i,2,N+1) {
        int p; cin>>p>>typ[i];
        adj[p].pb(i);
        adj[i].pb(p);
    }
    Flat(1,-1);
    _timer = 0;
    FOR(i,1,R+1) if(sz(reg[i]) > BL) {
        IDs[i] = _timer++;
        dfs(1, -1, i, 0);
    }
    while(Q-->0) {
        int r1, r2;
        cin>>r1>>r2;
        if(sz(reg[r1]) > BL) cout << preans[IDs[r1]][r2] << nl;
        else {
            ll ans = 0;
            each(p, reg[r1]) {
                int u = IDtour[p];
                ans += upper_bound(all(reg[r2]), tout[u]) - lower_bound(all(reg[r2]), tin[u]);
            }
            cout << ans << nl;
        }
        cout.flush();
    }
}

int main() {
    setIO();

    int t=1;
    //cin>>t;
    while(t-->0) {
        solve();
    }

    return 0;
}

Compilation message (stderr)

regions.cpp: In function 'void setIO(std::string)':
regions.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((NAME + ".inp").c_str(),"r",stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
regions.cpp:38:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   38 |         freopen((NAME + ".out").c_str(),"w",stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 15 / 15
• Subtask 2: 85 / 85