Submission #718182

#	Time	Username	Problem	Language	Result	Execution time	Memory
718182		bLIC	Regions (IOI09_regions)	C++17	10 / 100	144 ms	3664 KiB

regions

/**
 *  Author: Anil Byar
**/

#include <bits/stdc++.h>
// #include <ext/pb_ds/assoc_container.hpp>
// #include <ext/pb_ds/tree_policy.hpp>

// using namespace __gnu_pbds;
using namespace std;

// template<class T>
// using ordered_set = tree<T, null_type, less_equal<T>, rb_tree_tag, tree_order_statistics_node_update> ordered_set;



#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define sz(x) (int)(x).size()
#define ft first
#define sd second
#define pb push_back

// Source: https://codeforces.com/blog/entry/68809
// { start
void __print(int x) {cerr << x;}
void __print(long x) {cerr << x;}
void __print(long long x) {cerr << x;}
void __print(unsigned x) {cerr << x;}
void __print(unsigned long x) {cerr << x;}
void __print(unsigned long long x) {cerr << x;}
void __print(float x) {cerr << x;}
void __print(double x) {cerr << x;}
void __print(long double x) {cerr << x;}
void __print(char x) {cerr << '\'' << x << '\'';}
void __print(const char *x) {cerr << '"' << x << '"';}
void __print(const string &x) {cerr << '"' << x << '"';}
void __print(bool x) {cerr << (x ? "true" : "false");}

template<typename T, typename V>
void __print(const pair<T, V> &x) {cerr << '{'; __print(x.first); cerr << ','; __print(x.second); cerr << '}';}
template<typename T>
void __print(const T &x) {int f = 0; cerr << '{'; for (auto &i: x) cerr << (f++ ? "," : ""), __print(i); cerr << "}";}
void _print() {cerr << "]\n";}
template <typename T, typename... V>
void _print(T t, V... v) {__print(t); if (sizeof...(v)) cerr << ", "; _print(v...);}
#ifndef ONLINE_JUDGE
#define debug(x...) cerr << "[" << #x << "] = ["; _print(x)
#else
#define debug(x...)
#endif
// } end


typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef vector<int> vi;
typedef vector<pii> vii;
typedef vector<ll> vl;
typedef vector<pll> vll;
typedef vector<vi> vvi;
typedef vector<vii> vvii;
typedef vector<vl> vvl;

#define dbg if(0)

const ll MOD = 1e9+7;
const ll MOD9 = 998244353;
const ll INFLL = 1e18+5;
const int INF = 1e9;

void printbit(int x, int len) {string s="\n";while(len--){s=((x%2)?'1':'0')+s;x/=2;} cout<<s;}
ll power(ll x, ll y, ll mod){if (y==0) return 1;ll ret = power(x, y/2, mod);ret *= ret;ret%=mod;if (y&1) ret *= x;return ret%mod;}
ll modinv(ll x, ll mod = MOD) {return power(x, mod-2, mod);}

template<class T>
istream& operator>>(istream&in, vector<T>&v){
    for (T& x:v) in>>x;
    return in;
}
template<class T>
ostream& operator<<(ostream&out, vector<T>&v){
    for (T& x:v) out<<x<<' ';
    cout<<'\n';
    return out;
}
// use ?: with brackets (?:)
// check for overflow
// think about dp


const int maxN = 2e4+5;
const int maxK = 2505;
const int B = 447;
int n, r, q;
vvi adj(maxN);
vi regof(maxN);
vvi timing(maxK);
vi st(maxN), en(maxN);
vvi reg(maxK);
vi indof(maxK);
vi heavy(maxK);
vi cont;
vvi ansforheavy;
int tim, hvy;

inline int regcont(int r){return sz(reg[r]);}

void dfs(int node){
    st[node] = tim++;
    if (heavy[regof[node]]){
        cont[indof[regof[node]]]++;
        assert(indof[regof[node]]<hvy);
    }
    timing[regof[node]].push_back(st[node]);
    for (int x:adj[node]){
        for (int i = 0;i<hvy;i++){
            ansforheavy[i][regof[x]] += cont[i];
        }
        dfs(x);
    }
    en[node] = tim;
    if (heavy[regof[node]]){
        cont[indof[regof[node]]]--;
    }
}

ll query(int r1, int r2){
    if (heavy[r1]) return ansforheavy[indof[r1]][r2];
    else {
        ll ans = 0;
        for (int x:reg[r1]){
            ans += lower_bound(all(timing[r2]), en[x])-upper_bound(all(timing[r2]), st[x]);
        }
        return ans;
    }
}

void solve(){
    cin>>n>>r>>q;
    cin>>regof[1];
    reg[regof[1]].push_back(1);
    for (int i = 2;i<=n;i++){
        int p;
        cin>>p>>regof[i];
        reg[regof[i]].push_back(i);
        adj[p].push_back(i);
    }
    
    for (int i = 1;i<=r;i++){
        if (regcont(i)>B){
            heavy[i] = true;
            indof[i] = hvy++;
        }
    }
    ansforheavy.assign(hvy, vi(r+1, 0));
    cont.assign(hvy, 0);
    dfs(1);
    for (int i = 1;i<=r;i++) {
        // debug(i, timing[i]);
    }
    while(q--){
        int r1, r2;
        cin>>r1>>r2;
        // debug(r1, timing[r1], r2, timing[r2]);
        cout<<query(r1, r2)<<endl;
        // fflush(stdout);
    }
}

int main() {
    // ios_base::sync_with_stdio(false);
    // cin.tie(nullptr);
    // cout.tie(nullptr);


// #ifndef ONLINE_JUDGE
//     freopen("input.in", "r", stdin);
//     freopen("output.out", "w", stdout);
//     freopen("debug.dbg", "w", stderr);
//     int tt = clock();
// #endif

    int t=1, i = 1;
    // cin>>t;
    while(t--){
        // cout<<"Case #"<<i++<<": ";
        solve();
        cout<<'\n';
    }
// #ifndef ONLINE_JUDGE
//     cerr << "TIME = " << (float)(clock() - tt)/CLOCKS_PER_SEC << endl;
//     tt = clock();
// #endif
}

Compilation message (stderr)

regions.cpp: In function 'int main()':
regions.cpp:185:14: warning: unused variable 'i' [-Wunused-variable]
  185 |     int t=1, i = 1;
      |              ^

• Subtask 1: 10 / 15
• Subtask 2: 0 / 85