# | Submission time | Handle | Problem | Language | Result | Execution time | Memory |
---|---|---|---|---|---|---|---|
75656 | 2018-09-10T16:37:50 Z | tmwilliamlin168 | Circle selection (APIO18_circle_selection) | C++14 | 0 ms | 0 KB |
#include <bits/stdc++.h> using namespace std; #define ll long long const int mxN=3e5; int n, p[mxN], a[mxN]; ll x[mxN], y[mxN], r[mxN]; unordered_map<ll, vector<int>> mp; void rs(int k) { mp.clear(); for(int i=0; i<n; ++i) if(a[i]==-1) mp[x[i]>>k<<32|y[i]>>k].push_back(i); } int main() { ios_base::sync_with_stdio(0); cin.tie(0); cin >> n; for(int i=0; i<n; ++i) { cin >> x[i] >> y[i] >> r[i], x+=6969, y+=696969; p[i]=i; } sort(p, p+n, [&](const int &a, const int &b) { return r[a]==r[b]?a<b:r[a]>r[b]; }); memset(a, -1, 4*n); for(int i=-1, k=30; i+1<n; --i, --k) { rs(k); while(++i<n&&r[p[i]]>=1<<(k-1)) { if(a[p[i]]!=-1) continue; for(ll b=(x[p[i]]>>k)-2; b<=(x[p[i]]>>k)+2; ++b) { for(ll c=(y[p[i]]>>k)-2; c<=(y[p[i]]>>k)+2; ++c) { auto mf=mp.find(b<<32|c); if(mf==mp.end()) continue; int ns=0; vector<int> &v=mf->second; for(int j=0; j<v.size(); ++j) { ll dx=x[p[i]]-x[v[j]], dy=y[p[i]]-y[v[j]], rs=r[p[i]]+r[v[j]]; if(dx*dx+dy*dy<=rs*rs) a[v[j]]=p[i]; else v[ns++]=v[j]; } v.resize(ns); } } } } for(int i=0; i<n; ++i) cout << a[i]+1 << " "; }