제출 #135900

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
135900		Kastanda	Roller Coaster Railroad (IOI16_railroad)	C++11	100 / 100	231 ms	25200 KiB

railroad

// ItnoE
#include<bits/stdc++.h>
#define x first
#define y second
using namespace std;
typedef long long ll;
const int N = 200005;
int P[N];
int Find(int v)
{
    return (P[v] < 0 ? v : (P[v] = Find(P[v])));
}
inline bool Merge(int v, int u)
{
    v = Find(v);
    u = Find(u);
    if (v == u)
        return 0;
    P[v] = u;
    return 1;
}
int64_t plan_roller_coaster(vector < int > S, vector < int > T)
{
    int n = (int)S.size();
    vector < pair < int , pair < int , int > > > A, E;
    for (int i = 0; i < n; i ++)
    {
        A.push_back({S[i], {1, i}});
        A.push_back({T[i], {-1, i}});
    }
    A.push_back({(int)1e9, {1, n}});
    A.push_back({1, {-1, n ++}});
    sort(A.begin(), A.end());
    int SM = 0;
    ll tot = 0;
    memset(P, -1, sizeof(P));
    for (int i = 0; i + 1 < (int)A.size(); i ++)
    {
        SM += A[i].y.x;
        tot += max(SM, 0) * (ll)(A[i + 1].x - A[i].x);
        E.push_back({A[i + 1].x - A[i].x, {A[i].y.y, A[i + 1].y.y}});
        if (A[i].x == A[i + 1].x || SM)
            Merge(A[i].y.y, A[i + 1].y.y);
    }
    sort(E.begin(), E.end());
    for (auto e : E)
        if (Merge(e.y.x, e.y.y))
            tot += e.x;
    return (tot);
}

• Subtask 1: 11 / 11
• Subtask 2: 23 / 23
• Subtask 3: 30 / 30
• Subtask 4: 36 / 36