Submission #389769

#	Time	Username	Problem	Language	Result	Execution time	Memory
389769		milleniumEeee	Palembang Bridges (APIO15_bridge)	C++14	22 / 100	83 ms	7492 KiB

bridge

#include <bits/stdc++.h>
#define fr first
#define sc second
#define pii pair<int, int>
#define pb push_back
#define szof(s) (int)s.size()
#define all(s) s.begin(), s.end()
#define fastInp ios_base::sync_with_stdio(0); cin.tie(0);
#define int long long
using namespace std;

const int MAXN = (int)2e5 + 5;
const int INF = 1e18;

pair <char, int> st[MAXN];
pair <char, int> fn[MAXN];

bool ok(int pos) {
	return (st[pos].first == fn[pos].first);	
}

vector <int> vec;

int check(int pos) {
	int sum = 0;
	for (int el : vec) {
		sum += abs(el - pos);
	}
	return sum;
}

signed main() {
	fastInp;
	int n, k;
	cin >> k >> n;
	assert(k == 1);
	int side = 0;
	int cnt = 0;
	for (int i = 1; i <= n; i++) {
		cin >> st[i].fr >> st[i].sc >> fn[i].fr >> fn[i].sc;
		if (ok(i)) {
			side += abs(st[i].sc - fn[i].sc);
		} else {
			cnt++;
			vec.pb(st[i].sc);
			vec.pb(fn[i].sc);			
		}
	}
	sort(all(vec));
	int l = 0, r = 1e9;
	while (r - l > 3) {
		int m1 = l + (r - l) / 3;
		int m2 = r - (r - l) / 3;
		if (check(m1) < check(m2)) {
			r = m2;
		} else {
			l = m1;
		}
	}
	int bridge = INF;
	for (int i = l; i <= r; i++) {
		bridge = min(bridge, check(i) + cnt);
	}
	cout << side + bridge;
}

/*
2 5
B 0 A 4
B 1 B 3
A 5 B 7
B 2 A 6
B 1 A 7
*/

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