Submission #783211

#	Time	Username	Problem	Language	Result	Execution time	Memory
783211		Kahou	Construction of Highway (JOI18_construction)	C++14	16 / 100	99 ms	724 KiB

construction

/* In the name of God, aka Allah */
#include<bits/stdc++.h>
using namespace std;
#define F first
#define S second
#define endl '\n'
#define mk make_pair
typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;

const int N = 5050;
int n, a[N], par[N], fen[N];
pii P[N];
pii E[N];

ll get(int i) {
        ll out = 0;
        for (; i > 0; i -= i&-i) out += fen[i];
        return out;
}
void upd(int i, int x) {
        for (; i <= n; i += i&-i) fen[i] += x;
}
void solve() {
        cin >> n;
        for (int u = 1; u <= n; u++) {
                cin >> a[u];
                P[u] = {a[u], u};
        }
        sort(P+1, P+n+1);
        int t = 0;
        for (int i = 1; i <= n; i++) {
                if (P[i].F != P[i-1].F) t++;
                a[P[i].S] = t;
        }
        for (int i = 1; i <= n-1; i++) {
                int u, v;
                cin >> u >> v;
                E[i] = {u, v};
                par[v] = u;
        }
        for (int i = 1; i <= n-1; i++) {
                int u = E[i].F;
                for (int x = 1; x <= n; x++) fen[x] = 0;
                ll out = 0;
                while (u) {
                        out += get(a[u]-1);
                        upd(a[u], 1);
                        u = par[u];
                }
                u = E[i].F;
                while (u) {
                        a[u] = a[E[i].S];
                        u = par[u];
                }
                cout << out << endl;
        }
}
int main() {
        ios::sync_with_stdio(0), cin.tie(0), cout.tie(0);
        solve();
        return 0;
}

• Subtask 1: 7 / 7
• Subtask 2: 9 / 9
• Subtask 3: 0 / 84