제출 #228818

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
228818		osaaateiasavtnl	Regions (IOI09_regions)	C++14	100 / 100	5995 ms	92204 KiB

regions

#include<bits/stdc++.h>
using namespace std;
#define ii pair <int, int>
#define app push_back
#define all(a) a.begin(), a.end()
#define bp __builtin_popcount
#define ll long long
#define mp make_pair
#define f first
#define s second
#define Time (double)clock()/CLOCKS_PER_SEC

const int N = 5e5 + 7, K = 400;

int n, R, q;
int color[N], par[N];
vector <int> tree[N], pos[N], who[N];
int l[N], r[N], ptr = 0;
void dfs(int u) {
    l[u] = ++ptr;
    pos[color[u]].app(l[u]);
    for (int v : tree[u]) {
        dfs(v);
    }   
    r[u] = ptr;
}   

vector <int> cl[N], cr[N];

signed main() {
    #ifdef HOME
    freopen("input.txt", "r", stdin);
    #endif
    cin >> n >> R >> q;
    cin >> color[1];
    for (int i = 2; i <= n; ++i) {
        cin >> par[i] >> color[i];
        tree[par[i]].app(i);
    }   
    for (int i = 1; i <= n; ++i)
        who[color[i]].app(i);
    dfs(1);
    for (int i = 1; i <= n; ++i) {
        cl[color[i]].app(l[i]);
        cr[color[i]].app(r[i]);
    }   
    for (int i = 1; i <= R; ++i) {
        sort(all(cl[i]));
        sort(all(cr[i]));
    }   
    map <ii, int> mem;
    while (q--) {
        int c1, c2;
        cin >> c1 >> c2;

        if (mem.find(mp(c1, c2)) != mem.end()) {
            cout << mem[mp(c1, c2)] << endl;
            continue;
        }

        int ans = 0;
        if (who[c2].size() > K) {
            vector <int> &a = pos[c2];
            for (int u : who[c1]) {
                ans += upper_bound(all(a), r[u]) - upper_bound(all(a), l[u]);
            }   
        }
        else {
            for (int u : who[c2]) {
                ans += (lower_bound(all(cl[c1]), l[u]) - cl[c1].begin()) - (lower_bound(all(cr[c1]), l[u]) - cr[c1].begin());
            }   
        }

        mem[mp(c1, c2)] = ans;
        cout << ans << endl;
        fflush(stdout);
    }   
}

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