| # | Time | Username | Problem | Language | Result | Execution time | Memory |
|---|---|---|---|---|---|---|---|
| 598629 | definitelynotmee | Fountain Parks (IOI21_parks) | C++17 | 0 ms | 0 KiB |
This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include "parks.h"
#include<bits/stdc++.h>
using namespace std;
#define ff first
#define ss second
#define all(x) x.begin(), x.end()
using ll = long long;
using pii = pair<int,int>;
using pll = pair<ll,ll>;
template<typename t>
using matrix = vector<vector<t>>;
int construct_roads(std::vector<int> x, std::vector<int> y) {
if (x.size() == 1) {
build({}, {}, {}, {});
return 1;
}
int n = x.size();
std::vector<int> u, v, a, b;
int dx[]{1,0,-1,0};
int dy[]{0,1,0,-1};
vector<int> pai(n);
int comp = n;
iota(all(pai),0);
auto find =[&](int id, auto f){
if(pai[id] == id)
return id;
return pai[id] = f(pai[id],f);
};
auto onion =[&](int a, int b){
int pa = find(a,find);
int pb = find(b,find);
if(pa != pb){
comp--;
u.push_back(a);
v.push_back(b);
}
pai[pa] = pb;
};
map<pii,int> fount;
for(int i = 0; i < n; i++)
fount[{x[i],y[i]}] = i;
for(int i = 0; i < n; i++){
for(int j = 0; j < 4; j++){
int xi = x[i] + dx[j]*2, yi = y[i]+dy[j]*2;
if(fount.count({xi,yi}))
onion(i,fount[{xi,yi}]);
}
}
if(comp > 1)
return 0;
set<pii> bench;
mt19937 rng(time(nullptr));
vector<int>o(n-1);
iota(all(o));
shuffle(all(o),rng);
for(int i : o){
int cx = (x[u[i]]+x[v[i]])>>1, cy = (y[u[i]]+y[v[i]])>>1;
bool ok = 0;
for(int j = 0; j < 4; j++){
int xi = cx + dx[j], yi = cy+dy[j];
if(!((xi&1)&&(yi&1)))
continue;
if(!bench.count({xi,yi})){
a.push_back(xi);
b.push_back(yi);
bench.insert({xi,yi});
ok = 1;
break;
}
}
if(!ok)
return 0;
}
build(u,v,a,b);
return 1;
}