Submission #961207

#	Time	Username	Problem	Language	Result	Execution time	Memory
961207		steveonalex	Regions (IOI09_regions)	C++17	100 / 100	3107 ms	47516 KiB

regions

#include <bits/stdc++.h>
 
using namespace std;
 
typedef long long ll;
typedef unsigned long long ull;
 
#define ALL(v) (v).begin(), (v).end()
#define MASK(i) (1LL << (i))
#define GETBIT(mask, i) (((mask) >> (i)) & 1)
 
// mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
mt19937_64 rng(1);
ll rngesus(ll l, ll r){return ((ull) rng()) % (r - l + 1) + l;}
 
ll max(ll a, ll b){return (a > b) ? a : b;}
ll min(ll a, ll b){return (a < b) ? a : b;}
 
ll LASTBIT(ll mask){return mask & (-mask);}
ll pop_cnt(ll mask){return __builtin_popcountll(mask);}
ll ctz(ll mask){return __builtin_ctzll(mask);}
ll clz(ll mask){return __builtin_clzll(mask);}
ll logOf(ll mask){return 63 - clz(mask);}
 
template <class T1, class T2>
    bool minimize(T1 &a, T2 b){
        if (a > b){a = b; return true;}
        return false;
    }
template <class T1, class T2>
    bool maximize(T1 &a, T2 b){
        if (a < b){a = b; return true;}
        return false;
    }
template <class T>
    void printArr(T& a, string separator = " ", string finish = "\n"){
        for(auto i: a) cout << i << separator;
        cout << finish;
    }
template <class T>
    void remove_dup(vector<T> &a){
        sort(ALL(a));
        a.resize(unique(ALL(a)) - a.begin());
    }
 
const int N = 2e5 + 69;
 
int n, R, q;
vector<int> graph[N];
int region[N];
 
int l[N], r[N];
int dfs_cnt = 0;
 
void dfs(int u){
    l[u] = r[u] = ++dfs_cnt;
    for(int v: graph[u]){
        dfs(v);
        r[u] = r[v];
    }
}
 
vector<int> in[N], out[N];
 
int main(void){
    ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
 
    cin >> n >> R >> q;
    cin >> region[1];
    for(int i = 2; i<=n; ++i){
        int j;
        cin >> j >> region[i];
 
        graph[j].push_back(i);
    }
 
    dfs(1);
 
    for(int i= 1; i<=n; ++i){
        in[region[i]].push_back(l[i]);
        out[region[i]].push_back(r[i]);
    }
 
    for(int i = 1; i<=R; ++i){
        sort(ALL(in[i]));
        sort(ALL(out[i]));
    }

 
    map<pair<int, int>, int> mp;
    while(q--){
        int r1, r2; cin >> r1 >> r2;
        pair<int, int> cur = {r1, r2};
        if (mp.count(cur)) {cout << mp[cur] << endl; continue;}
 
        ll ans = 0;
        if (in[r1].size() <= in[r2].size()){
            for(int i: in[r1]) {
                ans -= lower_bound(ALL(in[r2]), i) - in[r2].begin();
            }
            for(int i: out[r1]) {
                ans += upper_bound(ALL(in[r2]), i) - in[r2].begin();
            }
        }
        else{
            for(int i: in[r2]){
                ans -= (lower_bound(ALL(out[r1]), i) - out[r1].begin()) - (upper_bound(ALL(in[r1]), i) - in[r1].begin());
            }
        }
        cout << ans << endl;
        mp[cur] = ans;
    }
 
    return 0;
}

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