Submission #1058783

# Submission time Handle Problem Language Result Execution time Memory
1058783 2024-08-14T13:45:32 Z LittleOrange Fountain Parks (IOI21_parks) C++17
5 / 100
2323 ms 72976 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 0 ms 344 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 0 ms 392 KB Output is correct
8 Correct 0 ms 348 KB Output is correct
9 Correct 130 ms 33004 KB Output is correct
10 Correct 11 ms 3540 KB Output is correct
11 Correct 74 ms 17620 KB Output is correct
12 Correct 18 ms 5076 KB Output is correct
13 Correct 13 ms 6348 KB Output is correct
14 Correct 0 ms 348 KB Output is correct
15 Correct 1 ms 604 KB Output is correct
16 Correct 131 ms 33904 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 0 ms 344 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 0 ms 392 KB Output is correct
8 Correct 0 ms 348 KB Output is correct
9 Correct 130 ms 33004 KB Output is correct
10 Correct 11 ms 3540 KB Output is correct
11 Correct 74 ms 17620 KB Output is correct
12 Correct 18 ms 5076 KB Output is correct
13 Correct 13 ms 6348 KB Output is correct
14 Correct 0 ms 348 KB Output is correct
15 Correct 1 ms 604 KB Output is correct
16 Correct 131 ms 33904 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 2323 ms 72824 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 0 ms 344 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 0 ms 392 KB Output is correct
8 Correct 0 ms 348 KB Output is correct
9 Correct 130 ms 33004 KB Output is correct
10 Correct 11 ms 3540 KB Output is correct
11 Correct 74 ms 17620 KB Output is correct
12 Correct 18 ms 5076 KB Output is correct
13 Correct 13 ms 6348 KB Output is correct
14 Correct 0 ms 348 KB Output is correct
15 Correct 1 ms 604 KB Output is correct
16 Correct 131 ms 33904 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 2323 ms 72824 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 0 ms 344 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 0 ms 392 KB Output is correct
8 Correct 0 ms 348 KB Output is correct
9 Correct 130 ms 33004 KB Output is correct
10 Correct 11 ms 3540 KB Output is correct
11 Correct 74 ms 17620 KB Output is correct
12 Correct 18 ms 5076 KB Output is correct
13 Correct 13 ms 6348 KB Output is correct
14 Correct 0 ms 348 KB Output is correct
15 Correct 1 ms 604 KB Output is correct
16 Correct 131 ms 33904 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 2013 ms 55024 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 0 ms 344 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 0 ms 392 KB Output is correct
8 Correct 0 ms 348 KB Output is correct
9 Correct 130 ms 33004 KB Output is correct
10 Correct 11 ms 3540 KB Output is correct
11 Correct 74 ms 17620 KB Output is correct
12 Correct 18 ms 5076 KB Output is correct
13 Correct 13 ms 6348 KB Output is correct
14 Correct 0 ms 348 KB Output is correct
15 Correct 1 ms 604 KB Output is correct
16 Correct 131 ms 33904 KB Output is correct
17 Correct 307 ms 69048 KB Output is correct
18 Correct 774 ms 72976 KB Output is correct
19 Incorrect 2076 ms 54612 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 0 ms 344 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 0 ms 392 KB Output is correct
8 Correct 0 ms 348 KB Output is correct
9 Correct 130 ms 33004 KB Output is correct
10 Correct 11 ms 3540 KB Output is correct
11 Correct 74 ms 17620 KB Output is correct
12 Correct 18 ms 5076 KB Output is correct
13 Correct 13 ms 6348 KB Output is correct
14 Correct 0 ms 348 KB Output is correct
15 Correct 1 ms 604 KB Output is correct
16 Correct 131 ms 33904 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 2323 ms 72824 KB Solution announced impossible, but it is possible.
24 Halted 0 ms 0 KB -