Submission #1075643

#	Time	Username	Problem	Language	Result	Execution time	Memory
1075643		stdfloat	Palembang Bridges (APIO15_bridge)	C++17	100 / 100	288 ms	17660 KiB

bridge

#include <bits/stdc++.h>
using namespace std;

using ll = long long;

int main() {
    ios::sync_with_stdio(false); cin.tie(nullptr);
 
    int K, n;
    cin >> K >> n;
 
    ll sm = 0;
    vector<vector<int>> v;
    for (int i = 0; i < n; i++) {
        char p, q;
        int s, t;
        cin >> p >> s >> q >> t;
 
        if (p == q) sm += abs(t - s);
        else v.push_back({s + t, s, t});
    }

    if (v.empty()) return cout << sm, 0;
 
    sm += (int)v.size();
 
    if (K == 1) {
        vector<int> u;
        for (auto i : v) u.insert(u.end(), {i[1], i[2]});
        sort(u.begin(), u.end());

        for (int j = 0; j < (int)u.size(); j++) sm += (j < (int)u.size() >> 1 ? -1 : 1) * u[j];

        return cout << sm, 0;
    }

    sort(v.begin(), v.end());
    
    ll ss1 = 0, ss2 = 0, st1 = 0, st2 = 0;
    multiset<int> s1, s2, t1, t2;
    auto g = [&]() {
        if ((int)s1.size() > (int)s2.size() + 1) {
            ss2 += *--s1.end(); ss1 -= *--s1.end();
            s2.insert(*--s1.end()); s1.erase(--s1.end());
        }
        if ((int)s2.size() > (int)s1.size() + 1) {
            ss1 += *s2.begin(); ss2 -= *s2.begin();
            s1.insert(*s2.begin()); s2.erase(s2.begin());
        }

        if ((int)t1.size() > (int)t2.size() + 1) {
            st2 += *--t1.end(); st1 -= *--t1.end();
            t2.insert(*--t1.end()); t1.erase(--t1.end());
        }
        if ((int)t2.size() > (int)t1.size() + 1) {
            st1 += *t2.begin(); st2 -= *t2.begin();
            t1.insert(*t2.begin()); t2.erase(t2.begin());
        }
    };

    ss1 = v[0][1] + v[0][2];
    s1.insert({v[0][1], v[0][2]});
    for (int i = 1; i < (int)v.size(); i++) {
        for (auto k : {v[i][1], v[i][2]}) {
            if (t2.empty() || k < *t2.begin()) {
                st1 += k; t1.insert(k);
            }
            else {
                st2 += k; t2.insert(k);
            }

            g();
        }
    }

    ll mn = LLONG_MAX;
    for (int i = 1; i < (int)v.size(); i++) {
        mn = min(mn, (ll)s1.size() * *--s1.end() - ss1 + ss2 - (ll)s2.size() * *--s1.end() + (ll)t1.size() * *--t1.end() - st1 + st2 - (ll)t2.size() * *--t1.end());
        for (auto k : {v[i][1], v[i][2]}) {
            if (s2.empty() || k < *s2.begin()) {
                ss1 += k; s1.insert(k);
            }
            else {
                ss2 += k; s2.insert(k);
            }
            
            if (t1.find(k) != t1.end()) {
                st1 -= k; t1.erase(t1.find(k));
            }
            else {
                st2 -= k; t2.erase(t2.find(k));
            }
            g();
        }
    }

    cout << sm + mn;
}

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