Submission #552681

#	Time	Username	Problem	Language	Result	Execution time	Memory
552681		QwertyPi	Palembang Bridges (APIO15_bridge)	C++14	31 / 100	2077 ms	5120 KiB

bridge

#include <bits/stdc++.h>
#define fi first
#define se second
#define int long long
#define inf (1LL << 60)
using namespace std;

const int N = 1e5+1;
typedef pair<int, int> pii;
int d[N];

int f(int l, int r, int x){
	if(x < l) return l - x;
	if(x > r) return x - r;
	return 0;
}

int32_t main(){
	int k, n;
	cin >> k >> n;
	vector<pii> A;
	int add = 0;
	for(int i = 0; i < n; i++){
		char c1, c2; int p1, p2;
		cin >> c1 >> p1 >> c2 >> p2;
		add += abs(p2 - p1);
		if(c1 != c2) add++, A.push_back({min(p1, p2), max(p1, p2)});
	}
	
	int ans1 = 0, c1 = 0, p1 = 0, ans = 0, ans2 = inf;
	for(int i = 0; i < A.size(); i++){
		c1 += A[i].fi * 2;
	}
	ans1 = c1;
	int l = 0, r = A.size();
	vector<int> q;
	for(int i = 0; i < A.size(); i++){
		q.push_back(A[i].fi);
		q.push_back(A[i].se);
	}
	sort(q.begin(), q.end());
	for(int i = 0; i < A.size() * 2; i++){
		c1 += (q[i] - p1) * (l - r) * 2;
		p1 = q[i];
		ans1 = min(ans1, c1);
		r--;
	}
	if(k == 1){
		cout << add + ans1 << endl;
		return 0;
	}
	ans = add + ans1;
	n = A.size() * 2, k = A.size();
	for(int x1 = 0; x1 < n; x1++){
		for(int x2 = x1; x2 < n; x2++){
			int res = 0;
			for(int i = 0; i < k; i++){
				int f1 = f(A[i].fi, A[i].se, q[x1]), f2 = f(A[i].fi, A[i].se, q[x2]);
				res += min(f1, f2);
			}
			ans2 = min(ans2, res * 2);
		}
	}
	ans = min(ans, add + ans2);
	cout << ans << endl;
}

Compilation message (stderr)

bridge.cpp: In function 'int32_t main()':
bridge.cpp:31:19: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   31 |  for(int i = 0; i < A.size(); i++){
      |                 ~~^~~~~~~~~~
bridge.cpp:37:19: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   37 |  for(int i = 0; i < A.size(); i++){
      |                 ~~^~~~~~~~~~
bridge.cpp:42:19: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   42 |  for(int i = 0; i < A.size() * 2; i++){
      |                 ~~^~~~~~~~~~~~~~

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