Submission #599939

#	Time	Username	Problem	Language	Result	Execution time	Memory
599939		wiwiho	Rail (IOI14_rail)	C++14	100 / 100	80 ms	4480 KiB

rail

#include "rail.h"

#include <bits/stdc++.h>
#include <bits/extc++.h>

#define StarBurstStream ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
#define iter(a) a.begin(), a.end()
#define riter(a) a.rbegin(), a.rend()
#define lsort(a) sort(iter(a))
#define gsort(a) sort(riter(a))
#define pb(a) push_back(a)
#define eb(a) emplace_back(a)
#define pf(a) push_front(a)
#define ef(a) emplace_front(a)
#define pob pop_back()
#define pof pop_front()
#define mp(a, b) make_pair(a, b)
#define F first
#define S second
#define mt make_tuple
#define gt(t, i) get<i>(t)
#define tomax(a, b) ((a) = max((a), (b)))
#define tomin(a, b) ((a) = min((a), (b)))
#define topos(a) ((a) = (((a) % MOD + MOD) % MOD))
#define uni(a) a.resize(unique(iter(a)) - a.begin())
#define printv(a, b) {bool pvaspace=false; \
for(auto pva : a){ \
    if(pvaspace) b << " "; pvaspace=true;\
    b << pva;\
}\
b << "\n";}

using namespace std;
using namespace __gnu_pbds;

typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;

using pii = pair<int, int>;
using pll = pair<ll, ll>;
using pdd = pair<ld, ld>;
using tiii = tuple<int, int, int>;

const ll MOD = 1000000007;
const ll MAX = 2147483647;

template<typename A, typename B>
ostream& operator<<(ostream& o, pair<A, B> p){
    return o << '(' << p.F << ',' << p.S << ')';
}

ll ifloor(ll a, ll b){
    if(b < 0) a *= -1, b *= -1;
    if(a < 0) return (a - b + 1) / b;
    else return a / b;
}

ll iceil(ll a, ll b){
    if(b < 0) a *= -1, b *= -1;
    if(a > 0) return (a + b - 1) / b;
    else return a / b;
}

void findLocation(int n, int first, int location[], int stype[]){
    
    vector<int> pos(n, -1), dir(n);
    pos[0] = first;
    dir[0] = 1;
    vector<int> coor(1000000);
    coor[first] = 1;

    vector<int> d0(n), dr(n), dl(n);
    for(int i = 1; i < n; i++){
        d0[i] = getDistance(0, i);
    }
    int rv = min_element(d0.begin() + 1, d0.end()) - d0.begin();
    pos[rv] = pos[0] + d0[rv];
    dir[rv] = -1;
    coor[pos[rv]] = -1;
    for(int i = 0; i < n; i++){
        if(i == rv) continue;
        dr[i] = getDistance(rv, i);
    }

    int lv = 0;
    for(int i = 1; i < n; i++){
        if(i == rv) continue;
        if(dr[i] < dr[lv]) lv = i;
    }
    pos[lv] = pos[rv] - dr[lv];
    dir[lv] = 1;
    coor[pos[lv]] = 1;

    // pos[0] <= pos[lv] < pos[rv]
    // down  down down  none up
    
    dl[0] = getDistance(lv, 0);
    for(int i = 1; i < n; i++){
        dl[i] = d0[i] - (pos[lv] - pos[0]);
        //dl[i] = getDistance(lv, i);
    }

    vector<int> left, right;
    for(int i = 0; i < n; i++){
        if(i == lv || i == rv) continue;
        if(dl[i] < dr[i]) right.eb(i);
        else left.eb(i);
    }

    // right
    int lst = rv;
    sort(iter(right), [&](int x, int y){ return dl[x] < dl[y]; });
    for(int i : right){
        int dlst = getDistance(lst, i);
        int tu = pos[lst] - dlst;
        int td = pos[lv] + dl[i];
        
        // check u (to down)
        bool uok = [&](){
            if(tu <= pos[lv]) return false;
            int tmp = tu - pos[lv];
            if((dl[i] - tmp) % 2) return false;
            int x = (dl[i] - tmp) / 2;
            int road = pos[lv] + tmp + x;
            if(coor[road] != -1) return false;
            return true;
        }();

        if(!uok){
            pos[i] = td;
            dir[i] = -1;
            coor[pos[i]] = -1;
            lst = i;
        }
        else{
            pos[i] = tu;
            dir[i] = 1;
            coor[pos[i]] = 1;
        }
    }

    // left
    sort(iter(left), [&](int x, int y){ return dr[x] < dr[y]; });
    lst = rv;
    for(int i : left){
        int dlst = getDistance(lst, i);
        int tu = pos[rv] - dr[i];
        int td = pos[lst] + dlst;
        
        bool dok = [&](){
            if(td <= lst) return false;
            int tmp = pos[rv] - td;
            if((dr[i] - tmp) % 2) return false;
            int x = (dr[i] - tmp) / 2;
            int road = pos[rv] - tmp - x;
            if(coor[road] != 1) return false;
            return true;
        }();

        if(!dok){
            pos[i] = tu;
            dir[i] = 1;
            coor[pos[i]] = 1;
            lst = i;
        }
        else{
            pos[i] = td;
            dir[i] = -1;
            coor[pos[i]] = -1;
        }
    }

    for(int i = 0; i < n; i++){
        location[i] = pos[i];
        stype[i] = dir[i] == 1 ? 1 : 2;
    }

}

• Subtask 1: 8 / 8
• Subtask 2: 22 / 22
• Subtask 3: 26 / 26
• Subtask 4: 44 / 44