Submission #152408

#	Time	Username	Problem	Language	Result	Execution time	Memory
152408		tfg	Organizing the Best Squad (FXCUP4_squad)	C++17	100 / 100	2645 ms	97328 KiB

squad

#include "squad.h"

#include <vector>
#include <algorithm>
#include <cassert>

struct PT {
	typedef long long T;
	T x, y;
	PT(T xx = 0, T yy = 0) : x(xx), y(yy){}
	PT operator +(const PT &p) const { return PT(x+p.x,y+p.y); }
	PT operator -(const PT &p) const { return PT(x-p.x,y-p.y); }
	PT operator *(T c)         const { return PT(x*c,y*c);     }
	T operator *(const PT &p)  const { return x*p.x+y*p.y;     }
	T operator %(const PT &p)  const { return x*p.y-y*p.x;     }
	// be careful using this without eps!
	bool operator<(const PT &p)const { return x != p.x ? x < p.x : y < p.y; }
	bool operator==(const PT &p)const{ return x == p.x && y == p.y; }
};

std::vector<PT> splitHull(const std::vector<PT> &hull) {
	std::vector<PT> ans(hull.size());
	for(int i = 0, j = (int) hull.size()-1, k = 0; k < (int) hull.size(); k++) {
		if(hull[i] < hull[j]) {
			ans[k] = hull[i++];
		} else {
			ans[k] = hull[j--];
		}
	}
	return ans;
}

std::vector<PT> ConvexHull (std::vector<PT> pts, bool needs = true) {
	if(needs) {
		std::sort(pts.begin(), pts.end());
	}
	pts.resize(std::unique(pts.begin(), pts.end()) - pts.begin());
	if(pts.size() <= 1) return pts;
	std::vector<PT> ans(pts.size() + 2);
	int s = 0;
	for(int i = 0; i < (int) pts.size(); i++) {
		while(s > 1 && (pts[i] - ans[s - 2]) % (ans[s - 1] - ans[s - 2]) >= 0) {
			s--;
		}
		ans[s++] = pts[i];
	}
	for(int i = (int) pts.size() - 2, t = s + 1; i >= 0; i--) {
		while(s >= t && (pts[i] - ans[s - 2]) % (ans[s - 1] - ans[s - 2]) >= 0) {
			s--;
		}
		ans[s++] = pts[i];
	}
	ans.resize(s-1);
	return ans;
}

std::vector<PT> ConvexHull(const std::vector<PT> &a, const std::vector<PT> &b) {
	auto A = splitHull(a);
	auto B = splitHull(b);
	std::vector<PT> C(A.size() + B.size());
	std::merge(A.begin(), A.end(), B.begin(), B.end(), C.begin());
	return ConvexHull(C, false);
}

int maximizeScalarProduct(const std::vector<PT> &hull, PT vec) {
	int ans = 0;
	int n = hull.size();
	if(n < 20) {
		for(int i = 0; i < n; i++) {
			if(hull[i] * vec > hull[ans] * vec) {
				ans = i;
			}
		}
	} else {
		int diff = 1;
		if(hull[0] * vec == hull[1] * vec) {
			int l = 2, r = n - 1;
			while(l != r) {
				int mid = (l + r) / 2;
				if((hull[1] - hull[0]) * (hull[mid] - hull[0]) > 0 && (hull[1] - hull[0]) % (hull[mid] - hull[0]) == 0) {
					l = mid + 1;
				} else {
					r = mid;
				}
			}
			diff = l;
			//diff = 2;
		}
		if(hull[0] * vec < hull[diff] * vec) {
			int l = diff, r = n - 1;
			while(l != r) {
				int mid = (l + r + 1) / 2;
				if(hull[mid] * vec >= hull[mid - 1] * vec && hull[mid] * vec >= hull[0] * vec) {
					l = mid;
				} else {
					r = mid - 1;
				}
			}
			if(hull[0] * vec < hull[l] * vec) {
				ans = l;
			}
		} else {
			int l = diff, r = n - 1;
			while(l != r) {
				int mid = (l + r + 1) / 2;
				if(hull[mid] * vec >= hull[mid - 1] * vec || hull[mid - 1] * vec < hull[0] * vec) {
					l = mid;
				} else {
					r = mid - 1;
				}
			}
			if(hull[0] * vec < hull[l] * vec) {
				ans = l;
			}
		}
	}
	return ans;
}

bool comp(PT a, PT b){
	int hp1 = (a.x < 0 || (a.x==0 && a.y<0));
	int hp2 = (b.x < 0 || (b.x==0 && b.y<0));
	if(hp1 != hp2) return hp1 < hp2;
	long long R = a%b;
	if(R) return R > 0;
	return a*a < b*b;
}


std::vector<PT> minkowskiSum(const std::vector<PT> &a, const std::vector<PT> &b){
	if(a.empty() || b.empty()) return std::vector<PT>(0);
	std::vector<PT> ret;
	if(std::min(a.size(), b.size()) < 2){
		for(int i = 0; i < (int) a.size(); i++) {
			for(int j = 0; j < (int) b.size(); j++) {
				ret.push_back(a[i]+b[j]);
			}
		}
	}
	ret.push_back(a[0]+b[0]);
	PT p = ret.back();
	int pa = 0, pb = 0;
	while(pa + pb + 1 < a.size()+b.size()){
		if(pb == (int) b.size() || (pa < (int) a.size() && comp((a[(pa+1)%a.size()]-a[pa]),(b[(pb+1)%b.size()]-b[pb]))))
			p = p + (a[(pa+1)%a.size()]-a[pa]), pa++;
		else p = p + (b[(pb+1)%b.size()]-b[pb]), pb++;
		while(ret.size() >= 2 && (p-ret.back()) % (p-ret[(int)ret.size()-2]) == 0) {
			ret.pop_back();
		}
		ret.push_back(p);
	}
	return ret;
}

const int ms = 300300;
PT h1[ms], h2[ms], tmp[ms];

std::vector<PT> solve(int l, int r) {
	if(r - l <= 1) {
		return std::vector<PT>(0);
	}
	int mid = (l + r) / 2;
	std::vector<PT> ans = ConvexHull(solve(l, mid), solve(mid, r));
	std::vector<PT> other;
	{
		std::vector<PT> hull[2];
		for(int i = l; i < mid; i++) {
			hull[0].push_back(h1[i]);
		}
		for(int i = mid; i < r; i++) {
			hull[1].emplace_back(h2[i]);
		}
		other = minkowskiSum(ConvexHull(hull[0], false), ConvexHull(hull[1], false));
	}
	{
		std::vector<PT> hull[2];
		for(int i = l; i < mid; i++) {
			hull[0].push_back(h2[i]);
		}
		for(int i = mid; i < r; i++) {
			hull[1].emplace_back(h1[i]);
		}
		other = ConvexHull(other, minkowskiSum(ConvexHull(hull[0], false), ConvexHull(hull[1], false)));
	}
	std::merge(h1 + l, h1 + mid, h1 + mid, h1 + r, tmp + l);
	for(int i = l; i < r; i++) {
		h1[i] = tmp[i];
	}
	std::merge(h2 + l, h2 + mid, h2 + mid, h2 + r, tmp + l);
	for(int i = l; i < r; i++) {
		h2[i] = tmp[i];
	}
	return ConvexHull(ans, other);
}

std::vector<PT> tot;
void Init(std::vector<int> A, std::vector<int> D, std::vector<int> P){
	int N = A.size();
	for(int i = 0; i < N; i++) {
		h1[i] = PT(A[i], P[i]);
		h2[i] = PT(D[i], P[i]);
	}
	tot = solve(0, N);
}

long long BestSquad(int X, int Y){
	PT cur(X, Y);
	return cur * tot[maximizeScalarProduct(tot, cur)];
}

Compilation message (stderr)

squad.cpp: In function 'std::vector<PT> minkowskiSum(const std::vector<PT>&, const std::vector<PT>&)':
squad.cpp:143:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  while(pa + pb + 1 < a.size()+b.size()){
        ~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~

• Subtask 1: 19 / 19
• Subtask 2: 28 / 28
• Subtask 3: 53 / 53