Submission #1105149

#	Time	Username	Problem	Language	Result	Execution time	Memory
1105149		michified	Palembang Bridges (APIO15_bridge)	C++17	0 / 100	1 ms	436 KiB

bridge

#include <bits/stdc++.h>
#define ll long long
#define db double
#define imx INT_MAX
#define imn INT_MIN
#define lmx LLONG_MAX
#define lmn LLONG_MIN
#define lid id * 2 + 1
#define rid id * 2 + 2
using namespace std;
#include <ext/pb_ds/assoc_container.hpp> 
#include <ext/pb_ds/tree_policy.hpp> 
using namespace __gnu_pbds; 
#define ordered_set tree<int, null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update> 
#define ordered_llset tree<ll, null_type, less<ll>, rb_tree_tag, tree_order_statistics_node_update> 

const ll mod = 1e9 + 7;

struct pair_t {
    ll l, r;
};

int main() {
    // ifstream cin("fortmoo.in");
    // ofstream cout("fortmoo.out");

    int k, n, i, s, t;
    cin >> k >> n;
    char p, q;
    ll ans = 0;
    vector<pair_t> pairs;
    for (i = 0; i < n; i++) {
        cin >> p >> s >> q >> t;
        if (s > t) swap(s, t);
        ans += t - s;
        if (p != q) {
            pairs.push_back({s, t});
            ans++;
        }
    }
    sort(pairs.begin(), pairs.end(), [](const pair_t& a, const pair_t& b){return a.l + a.r == b.l + b.r ? a.l < b.l : a.l + a.r < b.l + b.r;});
    n = pairs.size();
    vector<ll> lbest(n), rbest(n);
    priority_queue<ll> lo;
    priority_queue<ll, vector<ll>, greater<ll>> hi;
    auto cmp1 = [](const pair_t& a, const pair_t& b){return a.l > b.l;};
    auto cmp2 = [](const pair_t& a, const pair_t& b){return a.r > b.r;};
    priority_queue<pair_t, vector<pair_t>, decltype(cmp2)> mid(cmp2);
    priority_queue<pair_t, vector<pair_t>, decltype(cmp1)> right(cmp1);
    ll leftcnt = 0, cur = 0, prevmed = 0, median;
    for (i = 0; i < n; i++) {
        hi.push(pairs[i].l);
        hi.push(pairs[i].r);
        while (hi.size() > lo.size()) {
            lo.push(hi.top());
            hi.pop();
        }
        median = lo.top();
        cur += (median - prevmed) * leftcnt * 2;
        cur -= (median - prevmed) * right.size() * 2;
        if (median >= pairs[i].r) {
            leftcnt++;
            cur += abs(median - pairs[i].r) * 2;
        } else if (median < pairs[i].l) {
            right.push(pairs[i]);
            cur += abs(pairs[i].l - median) * 2;
        } else mid.push(pairs[i]);
        while (not right.empty() and median > right.top().l) {
            cur += (median - right.top().l) * 2;
            mid.push(right.top());
            right.pop();
        }
        while (not mid.empty() and median > mid.top().r) {
            cur += (median - mid.top().r) * 2;
            leftcnt++;
            mid.pop();
        }
        lbest[i] = cur;
        prevmed = median;
    }

    reverse(pairs.begin(), pairs.end());
    for (i = 0; i < n; i++) {
        ll tmp = -pairs[i].l;
        pairs[i].l = -pairs[i].r + 7;
        pairs[i].r = tmp + 7;
    }
    while (not lo.empty()) lo.pop();
    while (not hi.empty()) hi.pop();
    while (not mid.empty()) mid.pop();
    while (not right.empty()) right.pop();
    leftcnt = 0, cur = 0, prevmed = 0, median;
    for (i = 0; i < n; i++) {
        hi.push(pairs[i].l);
        hi.push(pairs[i].r);
        while (hi.size() > lo.size()) {
            lo.push(hi.top());
            hi.pop();
        }
        median = lo.top();
        cur += (median - prevmed) * leftcnt * 2;
        cur -= (median - prevmed) * right.size() * 2;
        if (median >= pairs[i].r) {
            leftcnt++;
            cur += abs(median - pairs[i].r) * 2;
        } else if (median < pairs[i].l) {
            right.push(pairs[i]);
            cur += abs(pairs[i].l - median) * 2;
        } else mid.push(pairs[i]);
        while (not right.empty() and median > right.top().l) {
            cur += (median - right.top().l) * 2;
            mid.push(right.top());
            right.pop();
        }
        while (not mid.empty() and median > mid.top().r) {
            cur += (median - mid.top().r) * 2;
            leftcnt++;
            mid.pop();
        }
        rbest[n - i - 1] = cur;
        prevmed = median;
    }
    ll add = rbest[0];
    if (k == 1) {
        cout << ans + add;
        return 0;
    }
    for (i = 0; i < n - i; i++) add = min(add, lbest[i] + rbest[i + 1]);
    cout << ans + add;
    return 0;
}

Compilation message (stderr)

bridge.cpp: In function 'int main()':
bridge.cpp:92:46: warning: right operand of comma operator has no effect [-Wunused-value]
   92 |     leftcnt = 0, cur = 0, prevmed = 0, median;
      |                                              ^

• Subtask 1: 0 / 8
• Subtask 2: 0 / 14
• Subtask 3: 0 / 9
• Subtask 4: 0 / 32
• Subtask 5: 0 / 37