Submission #551060

#	Time	Username	Problem	Language	Result	Execution time	Memory
551060		PiejanVDC	Fountain Parks (IOI21_parks)	C++17	5 / 100	510 ms	34772 KiB

parks

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

int dx[4] = {2,0,-2,0};
int dy[4] = {0,2,0,-2};

struct S {
    int x,y;
    int dir;
}s_;

void build(vector<int> u, vector<int> v, vector<int> a, vector<int> b);

const int mxN = (int)2e5 + 5;

int construct_roads(std::vector<int> x, std::vector<int> y) {
    const int n = (int)x.size();
    map<pair<int,int>,int>mp;
    for(int i = 0 ; i < n ; i++)
        mp[{x[i],y[i]}] = i;
    vector<int>u(n-1),v(n-1),a(n-1),b(n-1);
    set<pair<int,int>>processed;

    stack<S>s;

    s_.x = x[0], s_.y = y[0], s_.dir = 0;
    processed.insert({x[0], y[0]});
    s.push(s_);

    int P = 0;
    while(!s.empty()) {
        auto node = s.top();
        s.pop();

        int x = node.x, y = node.y, dir = node.dir;
        bool in_order = 0;

        if(mp.count({x + dx[dir], y + dy[dir]})) in_order = 1;

        int i = dir;
        int ii = mp[{x,y}];

        do {
            if(mp.count({x + dx[i], y + dy[i]}) && !processed.count({x + dx[i], y + dy[i]})) {
                if(dx[i] == 0) {
                    if(!processed.count({x-1,y + dy[i]/2}))
                        a[P] = x-1, b[P] = y + dy[i]/2, u[P] = ii, v[P] = mp[{x + dx[i], y + dy[i]}], P++, s_.x = x + dx[i], s_.y = y + dy[i], s_.dir = i, s.push(s_), processed.insert({x + dx[i], y + dy[i]}),processed.insert({a[P],b[P]});
                    else if(!processed.count({x+1,y + dy[i]/2}))
                        a[P] = x+1, b[P] = y + dy[i]/2, u[P] = ii, v[P] = mp[{x + dx[i], y + dy[i]}], P++, s_.x = x + dx[i], s_.y = y + dy[i], s_.dir = i, s.push(s_), processed.insert({x + dx[i], y + dy[i]}),processed.insert({a[P],b[P]});
                } else {
                    if(!processed.count({x + dx[i]/2, y-1}))
                        a[P] = x + dx[i]/2, b[P] = y-1, u[P] = ii, v[P] = mp[{x + dx[i], y + dy[i]}], P++, s_.x = x + dx[i], s_.y = y + dy[i], s_.dir = i, s.push(s_), processed.insert({x + dx[i], y + dy[i]}),processed.insert({a[P],b[P]});
                    else if(!processed.count({x + dx[i]/2, y+1}))
                        a[P] = x + dx[i]/2, b[P] = y+1, u[P] = ii, v[P] = mp[{x + dx[i], y + dy[i]}], P++, s_.x = x + dx[i], s_.y = y + dy[i], s_.dir = i, s.push(s_), processed.insert({x + dx[i], y + dy[i]}),processed.insert({a[P],b[P]});
                }
            }
            if(in_order) i++,i%=4;
            else i--, i+=4, i%= 4;
        } while(i != dir);
    }

    if(P < n-1)
        return 0;

    build(u,v,a,b);
    return 1;
}

• Subtask 1: 5 / 5
• Subtask 2: 0 / 10
• Subtask 3: 0 / 15
• Subtask 4: 0 / 20
• Subtask 5: 0 / 20
• Subtask 6: 0 / 30