Submission #432711

#	Time	Username	Problem	Language	Result	Execution time	Memory
432711		MarcoMeijer	Roller Coaster Railroad (IOI16_railroad)	C++14	0 / 100	293 ms	29944 KiB

railroad

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

// macros
typedef long long ll;
typedef long double ld;
typedef pair<int, int> ii;
typedef pair<ll, ll> lll;
typedef tuple<int, int, int> iii;
typedef vector<int> vi;
typedef vector<ii> vii;
typedef vector<iii> viii;
typedef vector<ll> vll;
typedef vector<lll> vlll;
#define REP(a,b,c) for(int a=int(b); a<int(c); a++)
#define RE(a,c) REP(a,0,c)
#define RE1(a,c) REP(a,1,c+1)
#define REI(a,b,c) REP(a,b,c+1)
#define REV(a,b,c) for(int a=int(c-1); a>=int(b); a--)
#define FOR(a,b) for(auto& a : b)
#define all(a) a.begin(), a.end()
#define INF 1e9
#define EPS 1e-9
#define pb push_back
#define popb pop_back
#define fi first
#define se second
#define sz size()
mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());

const int N=(1<<18);

ii seg[N*2]; int laz[N*2];
void buildSeg(int p=1, int l=0, int r=N-1) {
    laz[p] = 0;
    if(l == r) {
        seg[p] = {0,l};
        return;
    }
    int m=(l+r)/2;
    buildSeg(p*2,l,m);
    buildSeg(p*2+1,m+1,r);
    seg[p] = min(seg[p*2], seg[p*2+1]);
}
void addSeg(int p, int v) {
    seg[p] = {seg[p].fi+v, seg[p].se};
}
void push(int p) {
    addSeg(p*2,laz[p]);
    addSeg(p*2+1,laz[p]);
    laz[p] = 0;
}
void addSeg(int i, int j, int v, int p=1, int l=0, int r=N-1) {
    if(j < i) return;
    if(j < l || i > r) return;
    if(i <= l && j >= r) {
        addSeg(p,v);
        return;
    }
    push(p);
    int m=(l+r)/2;
    addSeg(i,j,v,p*2,l,m);
    addSeg(i,j,v,p*2+1,m+1,r);
    seg[p] = min(seg[p*2], seg[p*2+1]);
}

ll plan_roller_coaster(vi s, vi t) {
    s.pb(1e9); t.pb(1);
    int n = s.size();

    // coördinate compression
    vi difx;
    RE(i,n) difx.pb(s[i]), difx.pb(t[i]);
    sort(all(difx));

    buildSeg();

    set<int> unused;
    RE(i,difx.size()-1) unused.insert(i);

    RE(i,n) {
        int mn = min(s[i],t[i]);
        int mx = max(s[i],t[i])-1;
        if(mx < mn) continue;
        while(true) {
            auto it = unused.lower_bound(mn);
            if(it == unused.end())
                break;
            int x = *it;
            if(x > mx)
                break;
            unused.erase(x);
        }
    }

    if(!unused.empty())
        return 2;
    
    RE(i,n) {
        if(s[i] < t[i]) {
            addSeg(s[i],t[i]-1,1);
        } else {
            addSeg(t[i],s[i]-1,-1);
        }
    }

    if(seg[0].fi < 0)
        return 1;

    return 0;
}

• Subtask 1: 0 / 11
• Subtask 2: 0 / 23
• Subtask 3: 0 / 30
• Subtask 4: 0 / 36