Submission #87799

#	Time	Username	Problem	Language	Result	Execution time	Memory
87799		KCSC	Palembang Bridges (APIO15_bridge)	C++14	100 / 100	165 ms	45988 KiB

bridge

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

const int DIM = 100005;

long long lst1[DIM], lst2[DIM];
vector<pair<int, int>> arr;

void insert(auto &lef, auto &rig, long long &lsum, long long &rsum, int x) {
	if (!lef.size() or x <= lef.top()) {
		lsum += x; lef.push(x); }
	else {
		rsum += x; rig.push(x); } }

void balance(auto &lef, auto &rig, long long &lsum, long long &rsum) {
	while ((int) rig.size() - (int) lef.size() > 1) {
		lsum += rig.top(); rsum -= rig.top(); lef.push(rig.top()); rig.pop(); }	
	while ((int) lef.size() - (int) rig.size() > 1) {
		rsum += lef.top(); lsum -= lef.top(); rig.push(lef.top()); lef.pop(); } }

void solve(long long lst[DIM]) {
	long long lsum = 0, rsum = 0;
	priority_queue<int, vector<int>, less<int>> lef;
	priority_queue<int, vector<int>, greater<int>> rig;
	for (int i = 1; i <= (int) arr.size(); ++i) {
		insert(lef, rig, lsum, rsum, arr[i - 1].first);
		insert(lef, rig, lsum, rsum, arr[i - 1].second);
		balance(lef, rig, lsum, rsum);
		lst[i] = 1LL * lef.top() * (lef.size() - rig.size()) - lsum + rsum; } }

int main(void) {
#ifdef HOME
	freopen("bridge.in", "r", stdin);
	freopen("bridge.out", "w", stdout);
#endif
	int k, n; cin >> k >> n;
	long long ans = 0;
	for (int i = 1; i <= n; ++i) {
		char c1, c2; int p1, p2; 
		cin >> c1 >> p1 >> c2 >> p2;
		if (c1 == c2) {
			ans += abs(p2 - p1); }
		else {
			arr.emplace_back(min(p1, p2), max(p1, p2)); } }
	sort(arr.begin(), arr.end(), 
		[](const pair<int, int> &p1, const pair<int, int> &p2) {
			return p1.first + p1.second < p2.first + p2.second; });
	solve(lst1); reverse(arr.begin(), arr.end()); solve(lst2);
	long long cst = (1LL << 50);
	for (int i = 0; i <= (int) arr.size(); ++i) {
		cst = min(cst, lst1[i] + lst2[arr.size() - i]); }
	if (k == 1) {
		cst = lst1[arr.size()]; }
	cout << ans + arr.size() + cst << endl;
	return 0; }

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