Submission #934172

# Submission time Handle Problem Language Result Execution time Memory
934172 2024-02-26T22:54:37 Z bobbilyking Regions (IOI09_regions) C++17
95 / 100
8000 ms 35484 KB
#pragma GCC target ("avx2")
#pragma GCC optimize ("O3")
#pragma GCC optimize ("unroll-loops")

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

typedef int ll;
typedef long double ld;
typedef pair<ll, ll> pl;
typedef vector<ll> vl;
#define FD(i, r, l) for(ll i = r; i > (l); --i)

#define K first
#define V second
#define G(x) ll x; cin >> x;
#define GD(x) ld x; cin >> x;
#define GS(s) string s; cin >> s;
#define EX(x) { cout << x << '\n'; exit(0); }
#define A(a) (a).begin(), (a).end()
#define F(i, l, r) for (ll i = l; i < (r); ++i)

template<typename A, typename B>
A& chmax(A &a, B b) { return a < b ? (a=b): a; }

template<typename A, typename B>
A& chmin(A &a, B b) { return a > b ? (a=b): a; }




const ll NN = 2e5 + 1;
// const ll HEAVYTH = 450;
const ll HEAVYTH = 1800;
const ll RR = 2.5e4 + 1;
const ll AMT = RR / HEAVYTH + 2;

ll label[NN], tin[NN], tout[NN];
vl people[RR];
vl adj[NN];

vl dfsorder;
vl heavies;


ll sz[NN];


void dfsinit(ll i) {
    static int time = 0;
    tin[i] = time++;
    dfsorder.push_back(i);
    sort(A(adj[i]), [&](ll a, ll b) {
        return sz[a] > sz[b];
    });
    for (auto x: adj[i]) dfsinit(x);
    tout[i] = time;
}


bool isPar(ll i, ll j) {
    return tin[i] <= tin[j] and tin[j] < tout[i];
}

ll heavyRoot[AMT][RR];

void solveHeavyRoot(ll ask, ll put) {
    // compute number of ask labels on path to root, add to ans 
    vl stk;
    ll cnt = 0;

    for (auto x: dfsorder) {
        while (stk.size() and !isPar(stk.back(), x)) {
            cnt -= label[stk.back()] == ask;
            stk.pop_back();
        }
        cnt += label[x] == ask;
        stk.push_back(x);

        heavyRoot[put][label[x]] += cnt;

    }
}

ll containsHeavy[AMT][RR];

void solveContainsHeavy(ll ask, ll put) {
    // compute number of ask in subtree, then add to answer 
    vl ans(dfsorder.size() + 1);
    FD(i, ll(dfsorder.size()) - 1, -1) {
        ll x = dfsorder[i];
        for (auto y: adj[x]) ans[x] += ans[y];
        ans[x] += label[x] == ask;
        
        containsHeavy[put][label[x]] += ans[x];
    }
}


namespace seg {
    typedef ll T;
    T id=0;
    T f(T a, T b) {return a+b;}

    T t[2 * NN];
    ll n=NN;  // array size

    void modify(ll p, T value) {  // set value at position p
      for (p+=n, t[p] = value; p /= 2;) t[p] = f(t[2*p], t[2*p+1]);
    }

    T query(ll l, ll r) { // fold f on interval [l, r)
      T resl=id, resr=id;
      for (l += n, r += n; l < r; l /= 2, r /= 2) {
        if (l&1) resl = f(resl, t[l++]);
        if (r&1) resr = f(t[--r], resr);
      }
      return f(resl, resr);
    }
}

int main(){
    ios_base::sync_with_stdio(false); cin.tie(0);
    
    G(n) G(r) G(q)
    
    cin >> label[1]; people[label[1]].push_back(1);

    vl p(n+1);
    F(i, 2, n+1) {
        G(par) cin >> label[i]; 
        adj[par].push_back(i);
        people[label[i]].push_back(i);

        p[i] = par;
    }

    FD(i, n, 1) sz[p[i]]+= ++sz[i];

    dfsinit(1);

    F(i, 1, r+1) if (people[i].size() >= HEAVYTH) {
        heavies.push_back(i);
    }

    F(i, 0, heavies.size()) {
        solveHeavyRoot(heavies[i], i);
    }

    F(i, 0, heavies.size()) {
        solveContainsHeavy(heavies[i], i);
    }

    // cout << heavies.size() << " vs " << r << endl;

    // exit(0);

    vl selfs(RR);

    F(i, 1, RR) if (people[i].size()) {
        for (auto x: people[i]) seg::modify(tin[x], 1);
        for (auto x: people[i]) selfs[i] += seg::query(tin[x], tout[x]);
        for (auto x: people[i]) seg::modify(tin[x], 0);
        selfs[i] -= people[i].size();
    }
    
    while (q--) {
        G(r1) G(r2)
        if (r1 == r2) {
            cout << selfs[r1] << endl;
            continue;
        }
        
        if (people[r1].size() >= HEAVYTH) {
            cout << heavyRoot[lower_bound(A(heavies), r1) - heavies.begin()][r2] << endl;
        } else if (people[r2].size() >= HEAVYTH) {
            cout << containsHeavy[lower_bound(A(heavies), r2) - heavies.begin()][r1] << endl;
        } else {
            for (auto x: people[r2]) seg::modify(tin[x], 1);
            ll ans = 0;
            for (auto x: people[r1]) ans += seg::query(tin[x], tout[x]);
            cout << ans << endl;
            for (auto x: people[r2]) seg::modify(tin[x], 0);
        }
    }
}

Compilation message

regions.cpp: In function 'int main()':
regions.cpp:22:37: warning: comparison of integer expressions of different signedness: 'll' {aka 'int'} and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   22 | #define F(i, l, r) for (ll i = l; i < (r); ++i)
      |                                     ^
regions.cpp:147:5: note: in expansion of macro 'F'
  147 |     F(i, 0, heavies.size()) {
      |     ^
regions.cpp:22:37: warning: comparison of integer expressions of different signedness: 'll' {aka 'int'} and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   22 | #define F(i, l, r) for (ll i = l; i < (r); ++i)
      |                                     ^
regions.cpp:151:5: note: in expansion of macro 'F'
  151 |     F(i, 0, heavies.size()) {
      |     ^
# Verdict Execution time Memory Grader output
1 Correct 3 ms 10840 KB Output is correct
2 Correct 4 ms 10840 KB Output is correct
3 Correct 4 ms 10836 KB Output is correct
4 Correct 4 ms 10844 KB Output is correct
5 Correct 8 ms 11124 KB Output is correct
6 Correct 12 ms 10928 KB Output is correct
7 Correct 21 ms 10916 KB Output is correct
8 Correct 30 ms 10932 KB Output is correct
9 Correct 43 ms 11420 KB Output is correct
10 Correct 67 ms 11320 KB Output is correct
11 Correct 129 ms 11608 KB Output is correct
12 Correct 166 ms 12336 KB Output is correct
13 Correct 191 ms 11748 KB Output is correct
14 Correct 393 ms 12120 KB Output is correct
15 Correct 646 ms 15028 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 2197 ms 17288 KB Output is correct
2 Correct 2159 ms 15932 KB Output is correct
3 Correct 4487 ms 19400 KB Output is correct
4 Correct 423 ms 12120 KB Output is correct
5 Correct 445 ms 14208 KB Output is correct
6 Correct 2360 ms 13352 KB Output is correct
7 Correct 3222 ms 14132 KB Output is correct
8 Correct 3865 ms 19872 KB Output is correct
9 Correct 5212 ms 19004 KB Output is correct
10 Execution timed out 8012 ms 24892 KB Time limit exceeded
11 Correct 6794 ms 18232 KB Output is correct
12 Correct 1777 ms 22756 KB Output is correct
13 Correct 2375 ms 23264 KB Output is correct
14 Correct 4345 ms 22736 KB Output is correct
15 Correct 5866 ms 27872 KB Output is correct
16 Correct 5939 ms 35484 KB Output is correct
17 Correct 6804 ms 33696 KB Output is correct