Submission #474417

#	Time	Username	Problem	Language	Result	Execution time	Memory
474417		Gomango999	Palembang Bridges (APIO15_bridge)	C++14	100 / 100	258 ms	23000 KiB

bridge

#include "bits/stdc++.h"

using namespace std;

using ll = long long;

struct median {
    multiset<int> l, r;
    int total = 0;
    ll leftC = 0, rightC = 0;
    void insert(int c) {
        total++;
        if (r.empty() || c < *r.begin()) {
            l.insert(c);
            leftC += c;

        } else {
            r.insert(c);
            rightC += c;
        }

        if (l.size() < r.size()) {
            int cur = *r.begin();
            r.erase(r.find(cur));
            rightC -= cur;
            leftC += cur;
            l.insert(cur);
        } else if (r.size() + 1 < l.size()) {
            int cur = *l.rbegin();
            l.erase(l.find(cur));
            leftC -= cur;
            rightC += cur;
            r.insert(cur);
        }
    }

    ll query() {
        return rightC - leftC;
    }
};

int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);
//    freopen("", "r", stdin);
//    freopen("", "w", stdout);
    int n, k; cin >> k >> n;
    ll over = 0;
    vector<pair<int, int>> v;
    for (int i = 0; i < n; i++) {
        char a, b; int c, d; cin >> a >> c >> b >> d;
        if (a == b) {
            over += abs(c - d);
        } else {
            v.push_back({c, d});
        }
    }

    sort(v.begin(), v.end(), [](pair<int, int> a, pair<int, int> b) {
        return (a.first + a.second) / 2 < (b.first + b.second) / 2;
    });

    median m1;

    vector<ll> psum(n+1);

    for (int i = 0; i < v.size(); i++) {
        m1.insert(v[i].first);
        m1.insert(v[i].second);
        psum[i] = m1.query();
    }

    ll ans = m1.query();

    median m2;
    if (k == 1) cout << over + ans + v.size() << endl;
    else {
        for (int i = v.size()-1; i > 0; i--) {
            m2.insert(v[i].first);
            m2.insert(v[i].second);
            ans = min(ans, psum[i-1] + m2.query());
        }

        cout << ans + over + v.size() << endl;
        return 0;
    }

}

Compilation message (stderr)

bridge.cpp: In function 'int main()':
bridge.cpp:67:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   67 |     for (int i = 0; i < v.size(); i++) {
      |                     ~~^~~~~~~~~~

• Subtask 1: 8 / 8
• Subtask 2: 14 / 14
• Subtask 3: 9 / 9
• Subtask 4: 32 / 32
• Subtask 5: 37 / 37