Submission #1058781

# Submission time Handle Problem Language Result Execution time Memory
1058781 2024-08-14T13:44:29 Z LittleOrange Fountain Parks (IOI21_parks) C++17
5 / 100
2907 ms 71832 KB
#include "parks.h"
#include<bits/stdc++.h>
using namespace std;
using ll = int;
struct dsu{
    ll n;
    vector<ll> p;
    dsu(ll N):n(N),p(N,-1){}
    ll g(ll i){
        return p[i]<0?i:p[i]=g(p[i]);
    }
    bool m(ll a, ll b){
        a = g(a);
        b = g(b);
        if(a==b) return false;
        if(p[a]>p[b]) swap(a,b);
        p[a]+=p[b];
        p[b]=a;
        return true;
    }
};
struct obj{
    ll x,y,i;
    bool operator<(const obj &o) const{
        return x!=o.x?x<o.x:y<o.y;
    }
    obj operator+(const obj &o) const{
        return {x+o.x,y+o.y,i};
    }
    obj operator-(const obj &o) const{
        return {x-o.x,y-o.y,i};
    }
    bool operator==(const obj &o) const{
        return x==o.x&&y==o.y;
    }
    bool operator!=(const obj &o) const{
        return x!=o.x||y!=o.y;
    }
    obj turn() const{
        return {y,-x,i};
    }
};
using pos = obj;
ostream& operator<<(ostream& o, const pos &p){
    return o << "(" << p.x << "," << p.y << ";" << p.i << ")";
}
pos mid(const pos &a, const pos &b){
    return {(a.x+b.x)/2,(a.y+b.y)/2,0};
}
array<pos,2> mids(const pos &a, const pos &b){
    pos m = mid(a,b);
    array<pos,2> r = {m+(a-m).turn(),m+(b-m).turn()};
    ////cerr << "mids of " << a << " " << b << " -> " << r[0] << " " << r[1] << "\n";
    return r;
}
int construct_roads(std::vector<int> x, std::vector<int> y) {
    mt19937_64 mt(random_device{}());
    ll n = x.size();
    vector<obj> fs = {{0,2,0},{0,-2,0},{2,0,0},{-2,0,0}};
    if (x.size() == 1) {
	    build({}, {}, {}, {});
        return 1;
    }
    ll cnt = 10;
    while(cnt--){
        vector<ll> ans_u,ans_v,ans_a,ans_b;
        vector<obj> a(n);
        for(ll i = 0;i<n;i++){
            a[i] = {x[i],y[i],i};
        }
        //shuffle(ord.begin(),ord.end(),mt);
        sort(a.begin(),a.end());
        dsu d(n);
        vector<pair<pos,pos>> cons;
        vector<pair<pos,pos>> ord;
        for(pos u : a){
            for(pos f : fs){
                pos v = u+f;
                auto it = lower_bound(a.begin(),a.end(),v);
                if (it==a.end()||*it!=v) continue;
                v = *it;
                ord.push_back({u,v});
            }
        }
        shuffle(ord.begin(),ord.end(),mt);
        for(auto [u,v] : ord){
            if(d.m(u.i,v.i)){
                //cerr << "con " << u << " " << v << "\n";
                cons.push_back({u,v});
            }
        }
        if(cons.size()<n-1) return 0;
        vector<pos> v;
        for(auto [p0,p1] : cons){
            for(pos p : mids(p0,p1)) v.push_back(p);
        }
        sort(v.begin(),v.end());
        v.erase(unique(v.begin(),v.end()),v.end());
        ll m = v.size();
        vector<pair<pos,pos>> ops;
        vector<vector<ll>> con(m);
        vector<ll> u(n-1,0);
        for(auto [p0,p1] : cons){
            auto o = mids(p0,p1);
            ll i = lower_bound(v.begin(),v.end(),o[0])-v.begin();
            ll j = lower_bound(v.begin(),v.end(),o[1])-v.begin();
            pair<pos,pos> op = {min(o[0],o[1]),max(o[0],o[1])};
            //cerr << "ops " << op.first << " " << op.second << "\n";
            ops.push_back(op);
            con[i].push_back(j);
            con[j].push_back(i);
        }
        sort(ops.begin(),ops.end());
        vector<ll> idl(m);
        iota(idl.begin(),idl.end(),0);
        //sort(idl.begin(),idl.end(),[&](ll i, ll j){return con[i].size()<con[j].size();});
        shuffle(idl.begin(),idl.end(),mt);
        for(ll i : idl){
            shuffle(con[i].begin(),con[i].end(),mt);
            for(ll j : con[i]){
                pair<pos,pos> op = {min(v[i],v[j]),max(v[i],v[j])};
                //cerr << "test " << op.first << " " << op.second << "\n";
                auto it = lower_bound(ops.begin(),ops.end(),op);
                if (it==ops.end()) {
                    //cerr << "error 1\n";
                    continue;
                }
                //cerr << "got " << (*it).first << " " << (*it).second << "\n";
                if ((*it)!=op) {
                    //cerr << "error 2\n";
                    continue;
                }
                ll idx = it-ops.begin();
                //cerr << "idx= " << idx << "\n";
                if(u[idx]) {
                    //cerr << "error 3\n";
                    continue;
                }
                u[idx] = 1;
                pos p = v[i];
                ans_a.push_back(p.x);
                ans_b.push_back(p.y);
                auto os = mids(v[i],v[j]);
                //cerr << "use " << p << " from " << os[0] << " " << os[1] << "\n";
                ll idx1 = (*lower_bound(a.begin(),a.end(),os[0])).i;
                ll idx2 = (*lower_bound(a.begin(),a.end(),os[1])).i;
                ans_u.push_back(idx1);
                ans_v.push_back(idx2);
                break;
            }
        }
        if(ans_u.size()<n-1) continue;
        build(ans_u,ans_v,ans_a,ans_b);
        return 1;
    }
    return 0;
}

Compilation message

parks.cpp: In function 'int construct_roads(std::vector<int>, std::vector<int>)':
parks.cpp:92:23: warning: comparison of integer expressions of different signedness: 'std::vector<std::pair<obj, obj> >::size_type' {aka 'long unsigned int'} and 'll' {aka 'int'} [-Wsign-compare]
   92 |         if(cons.size()<n-1) return 0;
      |            ~~~~~~~~~~~^~~~
parks.cpp:152:24: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'll' {aka 'int'} [-Wsign-compare]
  152 |         if(ans_u.size()<n-1) continue;
      |            ~~~~~~~~~~~~^~~~
# Verdict Execution time Memory Grader output
1 Correct 1 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 1 ms 348 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 0 ms 348 KB Output is correct
8 Correct 0 ms 348 KB Output is correct
9 Correct 164 ms 33796 KB Output is correct
10 Correct 14 ms 3748 KB Output is correct
11 Correct 84 ms 17596 KB Output is correct
12 Correct 21 ms 5072 KB Output is correct
13 Correct 14 ms 6348 KB Output is correct
14 Correct 1 ms 348 KB Output is correct
15 Correct 1 ms 604 KB Output is correct
16 Correct 178 ms 33028 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 1 ms 348 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 0 ms 348 KB Output is correct
8 Correct 0 ms 348 KB Output is correct
9 Correct 164 ms 33796 KB Output is correct
10 Correct 14 ms 3748 KB Output is correct
11 Correct 84 ms 17596 KB Output is correct
12 Correct 21 ms 5072 KB Output is correct
13 Correct 14 ms 6348 KB Output is correct
14 Correct 1 ms 348 KB Output is correct
15 Correct 1 ms 604 KB Output is correct
16 Correct 178 ms 33028 KB Output is correct
17 Correct 0 ms 348 KB Output is correct
18 Correct 0 ms 348 KB Output is correct
19 Correct 0 ms 348 KB Output is correct
20 Correct 0 ms 348 KB Output is correct
21 Correct 0 ms 348 KB Output is correct
22 Correct 0 ms 348 KB Output is correct
23 Incorrect 2907 ms 70648 KB Solution announced impossible, but it is possible.
24 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 1 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 1 ms 348 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 0 ms 348 KB Output is correct
8 Correct 0 ms 348 KB Output is correct
9 Correct 164 ms 33796 KB Output is correct
10 Correct 14 ms 3748 KB Output is correct
11 Correct 84 ms 17596 KB Output is correct
12 Correct 21 ms 5072 KB Output is correct
13 Correct 14 ms 6348 KB Output is correct
14 Correct 1 ms 348 KB Output is correct
15 Correct 1 ms 604 KB Output is correct
16 Correct 178 ms 33028 KB Output is correct
17 Correct 0 ms 348 KB Output is correct
18 Correct 0 ms 348 KB Output is correct
19 Correct 0 ms 348 KB Output is correct
20 Correct 0 ms 348 KB Output is correct
21 Correct 0 ms 348 KB Output is correct
22 Correct 0 ms 348 KB Output is correct
23 Incorrect 2907 ms 70648 KB Solution announced impossible, but it is possible.
24 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 1 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 1 ms 348 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 0 ms 348 KB Output is correct
8 Correct 0 ms 348 KB Output is correct
9 Correct 164 ms 33796 KB Output is correct
10 Correct 14 ms 3748 KB Output is correct
11 Correct 84 ms 17596 KB Output is correct
12 Correct 21 ms 5072 KB Output is correct
13 Correct 14 ms 6348 KB Output is correct
14 Correct 1 ms 348 KB Output is correct
15 Correct 1 ms 604 KB Output is correct
16 Correct 178 ms 33028 KB Output is correct
17 Correct 0 ms 344 KB Output is correct
18 Correct 0 ms 348 KB Output is correct
19 Correct 0 ms 348 KB Output is correct
20 Incorrect 2587 ms 54984 KB Solution announced impossible, but it is possible.
21 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 1 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 1 ms 348 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 0 ms 348 KB Output is correct
8 Correct 0 ms 348 KB Output is correct
9 Correct 164 ms 33796 KB Output is correct
10 Correct 14 ms 3748 KB Output is correct
11 Correct 84 ms 17596 KB Output is correct
12 Correct 21 ms 5072 KB Output is correct
13 Correct 14 ms 6348 KB Output is correct
14 Correct 1 ms 348 KB Output is correct
15 Correct 1 ms 604 KB Output is correct
16 Correct 178 ms 33028 KB Output is correct
17 Correct 402 ms 67512 KB Output is correct
18 Correct 735 ms 71832 KB Output is correct
19 Incorrect 2614 ms 56400 KB Solution announced impossible, but it is possible.
20 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 1 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 1 ms 348 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 0 ms 348 KB Output is correct
8 Correct 0 ms 348 KB Output is correct
9 Correct 164 ms 33796 KB Output is correct
10 Correct 14 ms 3748 KB Output is correct
11 Correct 84 ms 17596 KB Output is correct
12 Correct 21 ms 5072 KB Output is correct
13 Correct 14 ms 6348 KB Output is correct
14 Correct 1 ms 348 KB Output is correct
15 Correct 1 ms 604 KB Output is correct
16 Correct 178 ms 33028 KB Output is correct
17 Correct 0 ms 348 KB Output is correct
18 Correct 0 ms 348 KB Output is correct
19 Correct 0 ms 348 KB Output is correct
20 Correct 0 ms 348 KB Output is correct
21 Correct 0 ms 348 KB Output is correct
22 Correct 0 ms 348 KB Output is correct
23 Incorrect 2907 ms 70648 KB Solution announced impossible, but it is possible.
24 Halted 0 ms 0 KB -