Submission #1050554

# Submission time Handle Problem Language Result Execution time Memory
1050554 2024-08-09T11:02:20 Z Zicrus Fountain Parks (IOI21_parks) C++17
0 / 100
0 ms 436 KB
#include <bits/stdc++.h>
#include "parks.h"
using namespace std;

typedef long long ll;

ll n;

int construct_roads(vector<int> x, vector<int> y) {
    n = x.size();
    unordered_map<ll, ll> pts;
    vector<pair<ll, ll>> edges;
    unordered_set<ll> hasEdge;
    for (int i = 0; i < n; i++) {
        ll hash = ((ll)x[i] << 31) | (ll)y[i];
        pts[hash] = i;
    }
    for (ll i = 0; i < n; i++) {
        ll hashL = (((ll)x[i]-2) << 31) | ((ll)y[i]);
        if (pts.count(hashL)) {
            ll hash = (min(i, pts[hashL]) << 31) | max(i, pts[hashL]);
            if (!hasEdge.count(hash)) {
                edges.push_back({i, pts[hashL]});
                hasEdge.insert(hash);
            }
        }
        ll hashR = (((ll)x[i]+2) << 31) | ((ll)y[i]);
        if (pts.count(hashR)) {
            ll hash = (min(i, pts[hashR]) << 31) | max(i, pts[hashR]);
            if (!hasEdge.count(hash)) {
                edges.push_back({i, pts[hashR]});
                hasEdge.insert(hash);
            }
        }
        ll hashD = (((ll)x[i]) << 31) | ((ll)y[i]-2);
        if (pts.count(hashD)) {
            ll hash = (min(i, pts[hashD]) << 31) | max(i, pts[hashD]);
            if (!hasEdge.count(hash)) {
                edges.push_back({i, pts[hashD]});
                hasEdge.insert(hash);
            }
        }
        ll hashU = (((ll)x[i]) << 31) | ((ll)y[i]+2);
        if (pts.count(hashU)) {
            ll hash = (min(i, pts[hashU]) << 31) | max(i, pts[hashU]);
            if (!hasEdge.count(hash)) {
                edges.push_back({i, pts[hashU]});
                hasEdge.insert(hash);
            }
        }
    }

    unordered_map<ll, ll> poss;
    unordered_map<ll, ll> lnk;
    vector<pair<ll, ll>> edgeHashes(edges.size());
    for (int i = 0; i < edges.size(); i++) {
        auto e = edges[i];
        ll midX = (x[e.first] + x[e.second]) / 2;
        ll midY = (y[e.first] + y[e.second]) / 2;
        ll leftX = midX - (midY - y[e.second]);
        ll leftY = midY + (midX - x[e.second]);
        ll rightX = midX + (midY - y[e.second]);
        ll rightY = midY - (midX - x[e.second]);
        ll hashL = (leftX << 31) | leftY;
        ll hashR = (rightX << 31) | rightY;
        poss[hashL]++;
        poss[hashR]++;
        lnk[hashL] ^= i;
        lnk[hashR] ^= i;
        edgeHashes[i] = {hashL, hashR};
    }

    vector<int> a(edges.size()), b(edges.size());
    queue<ll> q;
    for (auto &e : poss) {
        if (e.second != 1) continue;
        q.push(e.first);
    }
    ll cnt = 0;
    while (cnt < edges.size()) {
        while (!q.empty()) {
            ll hash = q.front(); q.pop();
            if (poss[hash] != 1) continue;
            cnt++;
            ll id = lnk[hash];
            a[id] = hash >> 31;
            b[id] = hash & ~(1 << 31);
            if (--poss[edgeHashes[id].first] == 1) q.push(edgeHashes[id].first);
            if (--poss[edgeHashes[id].second] == 1) q.push(edgeHashes[id].second);
            lnk[edgeHashes[id].first] ^= id;
            lnk[edgeHashes[id].second] ^= id;
        }
        if (cnt < edges.size()) {
            ll v = 0;
            for (auto &e : poss) {
                if (e.second != 2) continue;
                v = e.first;
                break;
            }
            bool has = false;
            for (int i = 0; i < edges.size(); i++) {
                auto e = edges[i];
                ll midX = (x[e.first] + x[e.second]) / 2;
                ll midY = (y[e.first] + y[e.second]) / 2;
                if (abs(midX - (v >> 31)) + abs(midY - (v & ~(1 << 31))) > 1) continue;
                if (!has) {
                    if (--poss[v] == 1) q.push(v);
                    lnk[v] ^= i;
                    has = true;
                    continue;
                }
                
            }
        }
    }

    vector<int> u, v;
    for (auto &e : edges) {
        u.push_back(e.first);
        v.push_back(e.second);
    }

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

Compilation message

parks.cpp: In function 'int construct_roads(std::vector<int>, std::vector<int>)':
parks.cpp:56:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   56 |     for (int i = 0; i < edges.size(); i++) {
      |                     ~~^~~~~~~~~~~~~~
parks.cpp:80:16: warning: comparison of integer expressions of different signedness: 'll' {aka 'long long int'} and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   80 |     while (cnt < edges.size()) {
      |            ~~~~^~~~~~~~~~~~~~
parks.cpp:93:17: warning: comparison of integer expressions of different signedness: 'll' {aka 'long long int'} and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   93 |         if (cnt < edges.size()) {
      |             ~~~~^~~~~~~~~~~~~~
parks.cpp:101:31: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  101 |             for (int i = 0; i < edges.size(); i++) {
      |                             ~~^~~~~~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 436 KB Output is correct
3 Incorrect 0 ms 344 KB Given structure is not connected: There is no path between vertices 0 and 1
4 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 436 KB Output is correct
3 Incorrect 0 ms 344 KB Given structure is not connected: There is no path between vertices 0 and 1
4 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 436 KB Output is correct
3 Incorrect 0 ms 344 KB Given structure is not connected: There is no path between vertices 0 and 1
4 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 436 KB Output is correct
3 Incorrect 0 ms 344 KB Given structure is not connected: There is no path between vertices 0 and 1
4 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 436 KB Output is correct
3 Incorrect 0 ms 344 KB Given structure is not connected: There is no path between vertices 0 and 1
4 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 436 KB Output is correct
3 Incorrect 0 ms 344 KB Given structure is not connected: There is no path between vertices 0 and 1
4 Halted 0 ms 0 KB -