Submission #1059004

#	Time	Username	Problem	Language	Result	Execution time	Memory
1059004		qwusha	Fountain Parks (IOI21_parks)	C++17	0 / 100	0 ms	600 KiB

parks

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
#define fi first
#define se second
typedef long double ld;
const ld eps = 1e-8;
mt19937 rnd(chrono::high_resolution_clock::now().time_since_epoch().count());
const ll inf = 1e18;
const ll mod = 1e9 + 7;

#include "parks.h"


vector<vector<int>> g;
vector<int> u, v, a, b;

vector<int> used;

void dfs(int ver) {
    used[ver] = 1;
    for (auto nod : g[ver]) {
        if (!used[nod]) {
            u.push_back(ver);
            v.push_back(nod);
            dfs(nod);
        }
    }
}

int construct_roads(vector<int> x, vector<int> y) {
    bool fir = 1, sec = 1, thi = 1;
    int n = x.size();
    for (int i = 0; i < n; i++) {
        if (x[i] != 2)
            fir = 0;
    }
    map<pair<int, int>, int> mp;
    for (int i = 0; i < n; i++) {
        mp[{x[i], y[i]}] = i;
    }
    g.resize(n);
    for (int i = 0; i < n; i++) {
        if (mp.find({x[i] - 2, y[i]}) != mp.end()) {
            g[i].push_back(mp[{x[i] - 2, y[i]}]);
        }
        if (mp.find({x[i] + 2, y[i]}) != mp.end()) {
            g[i].push_back(mp[{x[i] + 2, y[i]}]);
        }
        if (mp.find({x[i], y[i] - 2}) != mp.end()) {
            g[i].push_back(mp[{x[i], y[i] - 2}]);
        }
        if (mp.find({x[i], y[i] + 2}) != mp.end()) {
            g[i].push_back(mp[{x[i], y[i] + 2}]);
        }
    }
    used.resize(n);
    dfs(0);
    bool ch = 1;
    for (int i = 0; i < n; i++) {
        if (!used[i])
            ch = 0;
    }
    if (!ch)
        return 0;
    map<pair<int, int>, int> bench;
    map<pair<int, int>, set<int>> want;
    set<vector<int>> ben;
    for (int i = 0; i < v.size(); i++) {
        if (x[v[i]] == x[u[i]]) {
            want[{x[v[i]] + 1, y[v[i]] + y[u[i]] / 2}].insert(i);
            want[{x[v[i]] - 1, y[v[i]] + y[u[i]] / 2}].insert(i);
            bench[{x[v[i]] + 1, y[v[i]] + y[u[i]] / 2}]++;
            bench[{x[v[i]] - 1, y[v[i]] + y[u[i]] / 2}]++;
        } else {
            want[{x[v[i]] + x[u[i]] / 2, y[v[i]] + 1}].insert(i);
            want[{x[v[i]] + x[u[i]] / 2, y[v[i]] - 1}].insert(i);
            bench[{x[v[i]] + x[u[i]] / 2, y[v[i]] + 1}]++;
            bench[{x[v[i]] + x[u[i]] / 2, y[v[i]] - 1}]++;
        }
    }
    for (auto [pa, cnt] : bench) {
        ben.insert({cnt, pa.fi, pa.se});
    }
    a.resize(n - 1);
    b.resize(n - 1);
    while(!ben.empty()) {
        auto cur = *ben.begin();
        int i = *want[{cur[1], cur[2]}].begin();
        a[i] = cur[1];
        b[i] = cur[2];
        if (x[v[i]] == x[u[i]]) {
            want[{x[v[i]] + 1, y[v[i]] + y[u[i]] / 2}].erase(i);
            want[{x[v[i]] - 1, y[v[i]] + y[u[i]] / 2}].erase(i);
            ben.erase({bench[{x[v[i]] + 1, y[v[i]] + y[u[i]] / 2}], x[v[i]] + 1,y[v[i]] + y[u[i]] / 2});
            ben.erase({bench[{x[v[i]] - 1, y[v[i]] + y[u[i]] / 2}], x[v[i]] - 1, y[v[i]] + y[u[i]] / 2});
            bench[{x[v[i]] + 1, y[v[i]] + y[u[i]] / 2}]--;
            bench[{x[v[i]] - 1, y[v[i]] + y[u[i]] / 2}]--;
            if (bench[{x[v[i]] + 1, y[v[i]] + y[u[i]] / 2}] > 0) {
                ben.insert({bench[{x[v[i]] + 1, y[v[i]] + y[u[i]] / 2}], x[v[i]] + 1,y[v[i]] + y[u[i]] / 2});
            }
            if (bench[{x[v[i]] - 1, y[v[i]] + y[u[i]] / 2}] > 0) {
                ben.insert({bench[{x[v[i]] - 1, y[v[i]] + y[u[i]] / 2}], x[v[i]] - 1, y[v[i]] + y[u[i]] / 2});
            }
        } else {
            want[{x[v[i]] + x[u[i]] / 2, y[v[i]] + 1}].erase(i);
            want[{x[v[i]] + x[u[i]] / 2, y[v[i]] - 1}].erase(i);
            ben.erase({bench[{x[v[i]] + x[u[i]] / 2, y[v[i]] + 1}],x[v[i]] + x[u[i]] / 2, y[v[i]] + 1 });
            ben.erase({bench[{x[v[i]] + x[u[i]] / 2, y[v[i]] - 1}], x[v[i]] + x[u[i]] / 2, y[v[i]] - 1});
            bench[{x[v[i]] + x[u[i]] / 2, y[v[i]] + 1}]--;
            bench[{x[v[i]] + x[u[i]] / 2, y[v[i]] - 1}]--;
            if ( bench[{x[v[i]] + x[u[i]] / 2, y[v[i]] + 1}] > 0) {
                ben.insert({bench[{x[v[i]] + x[u[i]] / 2, y[v[i]] + 1}],x[v[i]] + x[u[i]] / 2, y[v[i]] + 1 });
            }
            if (bench[{x[v[i]] + x[u[i]] / 2, y[v[i]] - 1}] > 0) {
                ben.insert({bench[{x[v[i]] + x[u[i]] / 2, y[v[i]] - 1}], x[v[i]] + x[u[i]] / 2, y[v[i]] - 1});
            }
        }
    }
    build(u, v, a, b);
    return 1;

}




/*
int main() {
    vector<int> r = {0, 1, 1, 2, 2, 1, 2},
    u = {0, 0, 1, 1, 2, 3, 3, 4, 4, 5},
    v = {1, 2, 2, 3, 3, 4, 5, 5, 6, 6},
    c = {0, 0, 1, 0, 0, 1, 2, 0, 2, 1};

    auto res = find_reachable(r,u,v,c);
    for (int i = 0; i < r.size(); i++) {
        cout << res[i] << ' ';
    }
}
*/

Compilation message (stderr)

parks.cpp: In function 'int construct_roads(std::vector<int>, std::vector<int>)':
parks.cpp:69:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   69 |     for (int i = 0; i < v.size(); i++) {
      |                     ~~^~~~~~~~~~
parks.cpp:32:10: warning: variable 'fir' set but not used [-Wunused-but-set-variable]
   32 |     bool fir = 1, sec = 1, thi = 1;
      |          ^~~
parks.cpp:32:19: warning: unused variable 'sec' [-Wunused-variable]
   32 |     bool fir = 1, sec = 1, thi = 1;
      |                   ^~~
parks.cpp:32:28: warning: unused variable 'thi' [-Wunused-variable]
   32 |     bool fir = 1, sec = 1, thi = 1;
      |                            ^~~

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