Submission #670955

#	Time	Username	Problem	Language	Result	Execution time	Memory
670955		Dan4Life	Palembang Bridges (APIO15_bridge)	C++17	22 / 100	128 ms	9764 KiB

bridge

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

#define int long long
#define fi first
#define se second
#define pb push_back
using pii = pair<int,int>;
#define all(a) a.begin(),a.end()
#define sz(a) (int)a.size()
const int maxn = (int)1e5+10;
const int LINF = (int)1e18;
vector<int> v;
vector<pii> seg;
set<pii> bef,dur,aft;
int t, n, sum_bef, sum_dur, sum_aft, tot, ans=LINF;

int tryy(set<pii> &S, int bri, int t){
	if(S.empty()) return 0;
	vector<int> v; v.clear();
	int ans = LINF;
	for(auto u : S) v.pb(seg[u.se].fi), v.pb(seg[u.se].se);
	sort(all(v));
	int tot = (int)v.size();
	int med = v[tot/2];
	for(int i = tot/2-1; i < tot/2+1; i++){
		if(i<0 or i>=tot) continue;
		int med = v[i], sum=0;
		for(auto u : S){
			int x = seg[u.se].fi, y = seg[u.se].se;
			sum+=min(abs(med-x)+abs(med-y),abs(bri-x)+abs(bri-y))+1;
		}
		ans = min(ans, sum);
	}
	return ans;
}

int32_t main() {
	ios_base::sync_with_stdio(false); cin.tie(0);
	cin >> t >> n;
	for(int i = 0; i < n; i++){
		char a, c; int b, d;
		cin >> a >> b >> c >> d;
		if(a==c) tot+=abs(b-d);
		else seg.pb({b,d}), v.pb(b), v.pb(d);
	}
	sort(all(v)); sort(all(seg));
	v.erase(unique(all(v)), v.end());
	for(int i = 0; i < sz(seg); i++) 
		aft.insert({min(seg[i].fi, seg[i].se),i}), sum_aft+=seg[i].fi+seg[i].se+1;
	for(auto u : v){
		while(!aft.empty() and aft.begin()->fi<=u){
			int i = aft.begin()->se;
			dur.insert({max(seg[i].fi, seg[i].se), i}); 
			sum_dur+=abs(seg[i].se-seg[i].fi)+1;
			sum_aft-=seg[i].fi+seg[i].se+1;
			aft.erase(aft.begin());
		}

		while(!dur.empty() and dur.begin()->fi<u){
			int i = dur.begin()->se;
			bef.insert({max(seg[i].fi, seg[i].se), i}); 
			sum_bef+=seg[i].se+seg[i].fi+1;
			sum_dur-=abs(seg[i].se-seg[i].fi)-1;
			dur.erase(dur.begin());
		}
		ans = min(ans, (sz(bef)-sz(aft))*2*u-sum_bef+sum_dur+sum_aft);
		if(t==2){
			ans = min(ans, tryy(bef,u,0)+sum_dur+sum_aft-sz(aft)*2*u);
			ans = min(ans, sz(bef)*2*u-sum_bef+sum_dur+tryy(aft,u,1));
		}
	}
	if(seg.empty()) ans=0;
	cout << ans+tot;
}

Compilation message (stderr)

bridge.cpp: In function 'long long int tryy(std::set<std::pair<long long int, long long int> >&, long long int, long long int)':
bridge.cpp:25:6: warning: unused variable 'med' [-Wunused-variable]
   25 |  int med = v[tot/2];
      |      ^~~

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