Submission #1087509

# Submission time Handle Problem Language Result Execution time Memory
1087509 2024-09-12T19:07:32 Z M4mou Counting Mushrooms (IOI20_mushrooms) C++17
92.2449 / 100
9 ms 856 KB
/*
 * Solution with two mixed phases of dynamic size
 * By "mixed" we mean that new types are also detected in the second phase.
 * By "dynamic" we mean that #queries in the first phase is computed dynamically based on the current results.
 *
 * Author: Kian Mirjalali
 */
#include "mushrooms.h"
#include <cmath>
#include <algorithm>
#include <functional>
using namespace std;

#define allOf(c) ((c).begin()), ((c).end())

template<class C>
inline int largest_element_index(const vector<C>& v) {
	return max_element(allOf(v), [](const C& c1, const C& c2) {return c1.size()<c2.size();}) - v.begin();
}

/**
 * @returns ceil(a/b) for integers a, b
 */
template<class T>
inline T ceildiv(T a, T b) {
	return (a+b-1)/b;
}

/**
 * Finds minimum input of a function in range [begin, end).
 * @param f a function : Integer -> Real
 * @param begin
 * @param end
 * @returns Integer input which minimizes f
 */
inline int functionMinInput(function<double(int)> f, int begin, int end) {
	int best = begin;
	double fbest = f(best);
	for (int i = begin+1; i < end; i++) {
		const double fi = f(i);
		if (fbest > fi) {
			best = i;
			fbest = fi;
		}
	}
	return best;
}

typedef int Index;
typedef int SpeciesType;
const SpeciesType TYPE_0 = 0;
const SpeciesType TYPE_1 = 1;

typedef vector<Index> Indices;
class SpeciesTypes {
	vector<Indices> typesIndices;
public:
	inline SpeciesTypes(): typesIndices(2) {
	}
	inline void add(SpeciesType type, Index index) {
		typesIndices[type].push_back(index);
	}
	inline const Indices& getIndices(SpeciesType type) const {
		return typesIndices[type];
	}
	inline SpeciesType getLargestType() const {
		return largest_element_index(typesIndices);
	}
};

class SpeciesCounts {
	vector<int> counts;
public:
	inline SpeciesCounts(): counts({0, 0}) {
	}
	inline void add(SpeciesType type, int count=1, int otherCount=0) {
		counts[type] += count;
		counts[1-type] += otherCount;
	}
	inline int get(SpeciesType type) const {
		return counts[type];
	}
};

inline SpeciesType getType(Index i) {
	return use_machine({0, i});
}

Index a, b;
SpeciesType ta;
inline vector<SpeciesType> getTypes(Index i, Index j) {
	const int d = use_machine({a, i, b, j});
	return {(d>>1)^ta, (d&1)^ta};
}

int count_mushrooms(int n) {
	SpeciesTypes knownSpeciesTypes;
	Index head = 0;
	if (n >= 1) {
		knownSpeciesTypes.add(TYPE_0, head);
		head++;
		if (n >= 2) {
			const SpeciesType t1 = getType(head);
			knownSpeciesTypes.add(t1, head);
			head++;
			if (n == 2 || t1 == TYPE_0) {
				a = 0;
				b = 1;
				ta = TYPE_0;
			} else {//n >= 3 && t1 == TYPE_1
				const SpeciesType t2 = getType(head);
				knownSpeciesTypes.add(t2, head);
				head++;
				if (t2 == TYPE_0) {
					a = 0;
					b = 2;
					ta = TYPE_0;
				} else {//t2 == TYPE_1
					a = 1;
					b = 2;
					ta = TYPE_1;
				}
			}
		}
	}

	const int maxk = int(2*sqrt(n));
	while (head+2 <= n) {
		const SpeciesType majType = knownSpeciesTypes.getLargestType();
		const int majSize = knownSpeciesTypes.getIndices(majType).size();
		const auto rem_queries_func = [n, head, majSize] (int k) -> double {
			int l = 0;
			for (int s = n-head-2*k; s > 0;) {
				s -= max(majSize, k+ceildiv(head+l, 2));
				l++;
			}
			return k + l;
		};
		const int k = functionMinInput(rem_queries_func, 0, maxk);
		if (k == 0)
			break;
		const auto p = getTypes(head, head+1);
		knownSpeciesTypes.add(p[0], head);
		knownSpeciesTypes.add(p[1], head+1);
		head += 2;
	}

	SpeciesCounts speciesCounts;
	while (head < n) {
		const SpeciesType majType = knownSpeciesTypes.getLargestType();
		const Indices& majIndices = knownSpeciesTypes.getIndices(majType);
		const int majSize = majIndices.size();
		const int blockSize = min(majSize, n-head);
		Indices v(2*blockSize);
		for (int i = 0, j = 0; i < blockSize;) {
			v[j++] = head++;
			v[j++] = majIndices[i++];
		}
		const int differences = use_machine(v);
		knownSpeciesTypes.add((differences&1)^majType, v[0]);
		const int differents = (differences>>1);
		const int same = blockSize-1-differents;
		speciesCounts.add(majType, same, differents);
	}
	return knownSpeciesTypes.getIndices(TYPE_0).size()+speciesCounts.get(TYPE_0);
}
# Verdict Execution time Memory Grader output
1 Correct 0 ms 344 KB Output is correct
2 Correct 0 ms 344 KB Output is correct
3 Correct 0 ms 344 KB Output is correct
4 Correct 0 ms 344 KB Output is correct
5 Correct 0 ms 344 KB Output is correct
6 Correct 1 ms 344 KB Output is correct
7 Correct 4 ms 344 KB Output is correct
8 Correct 4 ms 456 KB Output is correct
9 Correct 6 ms 600 KB Output is correct
10 Correct 5 ms 344 KB Output is correct
11 Partially correct 6 ms 460 KB Output is partially correct
12 Correct 5 ms 344 KB Output is correct
13 Correct 4 ms 344 KB Output is correct
14 Correct 3 ms 468 KB Output is correct
15 Partially correct 6 ms 432 KB Output is partially correct
16 Partially correct 5 ms 344 KB Output is partially correct
17 Correct 3 ms 692 KB Output is correct
18 Correct 5 ms 600 KB Output is correct
19 Partially correct 9 ms 344 KB Output is partially correct
20 Correct 5 ms 344 KB Output is correct
21 Correct 5 ms 424 KB Output is correct
22 Partially correct 9 ms 460 KB Output is partially correct
23 Correct 7 ms 444 KB Output is correct
24 Correct 3 ms 344 KB Output is correct
25 Partially correct 5 ms 432 KB Output is partially correct
26 Partially correct 6 ms 344 KB Output is partially correct
27 Partially correct 6 ms 612 KB Output is partially correct
28 Partially correct 8 ms 444 KB Output is partially correct
29 Partially correct 8 ms 436 KB Output is partially correct
30 Partially correct 6 ms 344 KB Output is partially correct
31 Partially correct 5 ms 344 KB Output is partially correct
32 Partially correct 6 ms 456 KB Output is partially correct
33 Partially correct 6 ms 600 KB Output is partially correct
34 Partially correct 6 ms 344 KB Output is partially correct
35 Partially correct 6 ms 476 KB Output is partially correct
36 Partially correct 5 ms 452 KB Output is partially correct
37 Partially correct 6 ms 600 KB Output is partially correct
38 Partially correct 5 ms 476 KB Output is partially correct
39 Partially correct 6 ms 356 KB Output is partially correct
40 Partially correct 7 ms 484 KB Output is partially correct
41 Partially correct 6 ms 436 KB Output is partially correct
42 Partially correct 6 ms 344 KB Output is partially correct
43 Partially correct 9 ms 344 KB Output is partially correct
44 Partially correct 6 ms 344 KB Output is partially correct
45 Partially correct 6 ms 600 KB Output is partially correct
46 Partially correct 6 ms 344 KB Output is partially correct
47 Partially correct 9 ms 440 KB Output is partially correct
48 Partially correct 6 ms 340 KB Output is partially correct
49 Partially correct 6 ms 452 KB Output is partially correct
50 Partially correct 6 ms 344 KB Output is partially correct
51 Partially correct 8 ms 856 KB Output is partially correct
52 Partially correct 9 ms 344 KB Output is partially correct
53 Partially correct 6 ms 344 KB Output is partially correct
54 Partially correct 8 ms 344 KB Output is partially correct
55 Partially correct 5 ms 344 KB Output is partially correct
56 Partially correct 8 ms 344 KB Output is partially correct
57 Partially correct 6 ms 464 KB Output is partially correct
58 Partially correct 6 ms 600 KB Output is partially correct
59 Partially correct 6 ms 600 KB Output is partially correct
60 Partially correct 5 ms 344 KB Output is partially correct
61 Partially correct 8 ms 696 KB Output is partially correct
62 Correct 0 ms 344 KB Output is correct
63 Correct 0 ms 344 KB Output is correct
64 Correct 0 ms 344 KB Output is correct
65 Correct 0 ms 344 KB Output is correct
66 Correct 0 ms 344 KB Output is correct
67 Correct 0 ms 344 KB Output is correct
68 Correct 0 ms 344 KB Output is correct
69 Correct 0 ms 344 KB Output is correct
70 Correct 0 ms 344 KB Output is correct
71 Correct 0 ms 344 KB Output is correct
72 Correct 0 ms 344 KB Output is correct
73 Correct 0 ms 344 KB Output is correct
74 Correct 0 ms 344 KB Output is correct
75 Correct 1 ms 344 KB Output is correct
76 Correct 0 ms 344 KB Output is correct
77 Correct 0 ms 344 KB Output is correct
78 Correct 1 ms 344 KB Output is correct
79 Correct 0 ms 344 KB Output is correct
80 Correct 0 ms 344 KB Output is correct
81 Correct 0 ms 372 KB Output is correct
82 Correct 1 ms 344 KB Output is correct
83 Correct 0 ms 364 KB Output is correct
84 Correct 0 ms 344 KB Output is correct
85 Correct 0 ms 344 KB Output is correct
86 Correct 0 ms 344 KB Output is correct
87 Correct 0 ms 344 KB Output is correct
88 Correct 0 ms 344 KB Output is correct
89 Correct 0 ms 344 KB Output is correct
90 Correct 1 ms 344 KB Output is correct
91 Correct 0 ms 344 KB Output is correct