Submission #386820

#	Time	Username	Problem	Language	Result	Execution time	Memory
386820		wenqi	Palembang Bridges (APIO15_bridge)	C++14	0 / 100	2 ms	492 KiB

bridge

#include <bits/stdc++.h>

using namespace std;

using ll = long long;

#define all(x) begin(x), end(x)
#define fillc(p, t, v) fill_n((t*) p, sizeof(p) / sizeof(t), v)
#define pb push_back
#define f first
#define s second

int K, N;

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    cin >> K >> N;
    ll base = 0;
    vector<pair<ll, ll>> segs;
    for(int i = 0; i < N; i++) {
        char a, b;
        int x, y;
        cin >> a >> x >> b >> y;
        if(x > y) swap(x, y);
        if(a == b) {
            base += y - x;
        }else{
            base += y - x + 1; 
            segs.pb({x, y});
        }
    }
    sort(all(segs));
    vector<pair<ll, ll>> es;
    for(auto s : segs)
        es.pb({s.f, 0}), es.pb({s.s, 1});
    
    sort(all(es));

    auto D = es;
    
    D[D.size() - 1] = {0, 0};
    for(int i = es.size() - 2; i >= 0; i--) {
        D[i] = D[i + 1];
        if(es[i].s == 0) {
            D[i].f++;
            D[i].s += es[i].f;
        }
    }

    ll k = 0;
    ll n = 0;
    ll l = 0;
    ll ans = INT64_MAX;
    int i = 0;
    for(auto p : es) {
        k += 2 * n * (p.f - l);
        if(p.s == 0) {
            ll hm = k + 2 * (D[i].s - p.f * D[i].f);
            ans = min(ans, hm);
        }else{
            n++;
        }
        l = p.f;
        i++;
    }
    cout << base + ans << '\n';
    return 0;
}

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