Submission #197737

#	Time	Username	Problem	Language	Result	Execution time	Memory
197737		dolphingarlic	ČVENK (COI15_cvenk)	C++14	0 / 100	255 ms	96032 KiB

cvenk

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
 
ll tot_dist = 0, ans = LLONG_MAX;
 
struct Node {
    ll x, y, l;
    Node *c[2];
 
    Node(ll X = 0, ll Y = 0): x(X), y(Y), l(0) {
        c[0] = c[1] = NULL;
    }
 
    void insert(Node *ins, int child) {
        l++;
        if (!c[child]) {
            c[child] = ins;
            return;
        }
        ins->c[child] = c[child];
        ins->l += c[child]->l;
        c[child] = ins;
    }
};
 
int n;
Node *root = new Node();
 
void dfs(Node *curr) {
    ans = min(ans, tot_dist);
    for (int i = 0; i < 2; i++) {
        if (curr->c[i]) {
            ll dx = curr->x - curr->c[i]->x + curr->y - curr->c[i]->y;
            tot_dist += dx * (2 * curr->c[i]->l - n);
            dfs(curr->c[i]);
            tot_dist -= dx * (2 * curr->c[i]->l - n);
        }
    }
}

pair<ll, ll> a[100000];
bool cmp(pair<ll, ll> x, pair<ll, ll> y) { return x.first + x.second > y.first + y.second; }
 
int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cin >> n;
    for (int i = 0; i < n; i++) {
        cin >> a[i].first >> a[i].second;
        tot_dist += a[i].first + a[i].second;
    }
    sort(a, a + n, cmp);

    for (int i = 0; i < n; i++) {
        Node *curr = root;
        ll cx = 0, cy = 0;
        for (int j = 30; ~j; j--) {
            if (a[i].first & (1 << j)) {
                cx |= (1 << j);
                curr->insert(new Node(cx, cy), 0);
                curr = curr->c[0];
            } else if (a[i].second & (1 << j)) {
                cy |= (1 << j);
                curr->insert(new Node(cx, cy), 1);
                curr = curr->c[1];
            }
        }
        curr->l++;
    }
    dfs(root);
    cout << ans;
}

• Subtask 1: 0 / 17
• Subtask 2: 0 / 21
• Subtask 3: 0 / 22
• Subtask 4: 0 / 40