Submission #75662

#	Time	Username	Problem	Language	Result	Execution time	Memory
75662		tmwilliamlin168	Circle selection (APIO18_circle_selection)	C++14	64 / 100	3035 ms	38320 KiB

circle_selection

#include <bits/stdc++.h>
using namespace std;

#define ll long long
#define getchar_unlocked getchar
#define putchar_unlocked putchar

inline int in() {
	bool minus = false;
	int result = 0;
	char ch = getchar_unlocked();
	while(true) {
		if(ch == '-')
			break;
		if(ch >= '0' && ch <= '9')
			break;
		ch = getchar_unlocked();
	}
	if(ch == '-')
		minus = true;
	else
		result = ch-'0';
	while(true) {
		ch = getchar_unlocked();
		if (ch < '0' || ch > '9')
			break;
		result = result*10 + (ch - '0');
	}
	return minus?-result:result;
}
inline void out(int x) {
	int rev=x, c=0;
	while(!(rev%10)) {
		++c;
		rev/=10;
	}
	rev=0;
	while(x) {
		rev=rev*10+x%10;
		x/=10;
	}
	while(rev) {
		putchar_unlocked(rev%10+'0');
		rev/=10;
	}
	while(c--)
		putchar_unlocked('0');
}

const int mxN=3e5;
int n, p[mxN], p2[mxN], a[mxN];
ll x[mxN], y[mxN], r[mxN];
unordered_map<int, vector<array<int, 2>>> mp;

void rs(int k) {
	mp.clear();
	for(int i=0; i<n; ++i)
		if(a[p2[i]]==-1)
			mp[x[p2[i]]>>k].push_back({y[p2[i]]>>k, p2[i]});
}

int main() {
	n=in();
	for(int i=0; i<n; ++i) {
		x[i]=in(), y[i]=in(), r[i]=in();
		p[i]=p2[i]=i;
	}
	sort(p, p+n, [&](const int &a, const int &b) {
		return r[a]==r[b]?a<b:r[a]>r[b];
	});
	sort(p2, p2+n, [&](const int &a, const int &b) {
		return y[a]<y[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) {
				auto mf=mp.find(b);
				if(mf==mp.end())
					continue;
				vector<array<int, 2>> &v=mf->second;
				for(int j=lower_bound(v.begin(), v.end(), array<int, 2>{(y[p[i]]>>k)-2, 0})-v.begin(); j<v.size()&&v[j][0]<=(y[p[i]]>>k)+2; ++j) {
					ll dx=x[p[i]]-x[v[j][1]], dy=y[p[i]]-y[v[j][1]], rs=r[p[i]]+r[v[j][1]];
					if(dx*dx+dy*dy<=rs*rs&&a[v[j][1]]==-1)
						a[v[j][1]]=p[i];
				}
			}
		}
	}
	for(int i=0; i<n; ++i) {
		out(a[i]+1);
		putchar_unlocked(' ');
	}
}

Compilation message (stderr)

circle_selection.cpp: In function 'void rs(int)':
circle_selection.cpp:59:39: warning: narrowing conversion of '(y[p2[i]] >> k)' from 'long long int' to 'int' inside { } [-Wnarrowing]
    mp[x[p2[i]]>>k].push_back({y[p2[i]]>>k, p2[i]});
                               ~~~~~~~~^~~
circle_selection.cpp: In function 'int main()':
circle_selection.cpp:85:73: warning: narrowing conversion of '((y[p[i]] >> k) - 2)' from 'long long int' to 'int' inside { } [-Wnarrowing]
     for(int j=lower_bound(v.begin(), v.end(), array<int, 2>{(y[p[i]]>>k)-2, 0})-v.begin(); j<v.size()&&v[j][0]<=(y[p[i]]>>k)+2; ++j) {
                                                             ~~~~~~~~~~~~^~
circle_selection.cpp:85:93: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int j=lower_bound(v.begin(), v.end(), array<int, 2>{(y[p[i]]>>k)-2, 0})-v.begin(); j<v.size()&&v[j][0]<=(y[p[i]]>>k)+2; ++j) {
                                                                                            ~^~~~~~~~~

• Subtask 1: 7 / 7
• Subtask 2: 12 / 12
• Subtask 3: 15 / 15
• Subtask 4: 0 / 23
• Subtask 5: 30 / 30
• Subtask 6: 0 / 13