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ID题目提交者结果用时内存语言文件大小提交时间测评时间
#321757#6669. MapaUnknown15080 8ms3648kbC++202.9kb2024-02-05 11:46:402024-02-05 11:46:41

Judging History

你现在查看的是最新测评结果

  • [2024-02-05 11:46:41]
  • 评测
  • 测评结果:0
  • 用时:8ms
  • 内存:3648kb
  • [2024-02-05 11:46:40]
  • 提交

answer

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

void main_program();

signed main(){
	ios_base::sync_with_stdio(0); cin.tie(0);
	main_program();
}

const int mod = 1e9 + 7;

int binpow(int n, int a){
	int res = 1;
	for (int exp = n; a; a >>= 1, exp = 1LL * exp * exp % mod){
		if (a & 1) res = 1LL * res * exp % mod;
	}
	return res;
}

int inverse(int x){
	return binpow(x, mod - 2);
}

int player;
using Poly = vector<int>;

Poly multiply(const Poly &A, const Poly &B){
	// O(n^2) multiplication
	Poly res(A.size() + B.size() - 1);

	for (int i = 0; i < (int)A.size(); i++){
		for (int j = 0; j < (int)B.size(); j++){
			res[i + j] = (res[i + j] + 1LL * A[i] * B[j]) % mod;
		}
	}

	return res;
}

auto size_comp = [](Poly A, Poly B){ return A.size() > B.size(); };

Poly multiply(const vector<Poly> &V){
	priority_queue<Poly, vector<Poly>, decltype(size_comp)> pq(size_comp);

	for (Poly P: V) pq.push(P);
	while (pq.size() >= 2){
		Poly p1 = pq.top(); pq.pop();
		Poly p2 = pq.top(); pq.pop();
		pq.push(multiply(p1, p2));
	}

	return pq.top();
}

Poly lagrange(const vector<pair<int, int>> &V){
	int n = V.size();

	vector<int> X(n), Y(n);
	for (int i = 0; i < n; i++){
		tie(X[i], Y[i]) = V[i];
	}

	Poly total(n);
	for (int i = 0; i < n; i++){
		vector<Poly> vec; vec.reserve(n - 1);

		int num = Y[i];

		for (int j = 0; j < n; j++){
			if (j == i) continue;
			vec.push_back(Poly{-X[j], 1});
			num = 1LL * num * inverse(X[i] - X[j]) % mod;
		}

		Poly prod = multiply(vec);
		for (int j = 0; j < (int)prod.size(); j++){
			total[j] = (total[j] + 1LL * prod[j] * num) % mod;
		}
	}

	return total;
}

namespace encode {
	string convert(int x){
		if (x < 0) x += mod;
		string repr;
		for (int i = 29; i >= 0; i--){
			repr += ((x >> i) & 1) + '0';
		}
		return repr;
	}

	void solve(){
		int n; cin >> n;

		vector<pair<int, int>> vec(n);
		for (int i = 0; i < n; i++){
			cin >> vec[i].first >> vec[i].second;
		}

		Poly f = lagrange(vec);
		string answer;

		for (int i = 0; i < (int)f.size(); i++){
			answer += convert(f[i]);
		}

		cout << answer.size() << "\n" << answer << "\n";
	}
}

namespace decode {
	int convert(string s){
		int num = 0;
		for (int i = 0; i < 30; i++){
			int digit = (s[i] - '0');
			num = (num << 1) + digit;
		}
		return num;
	}

	int n, q, k;

	void solve(){
		cin >> n >> q >> k;
		string S; cin >> S;

		vector<int> f(n);
		for (int i = 0; i < n; i++){
			f[i] = convert(S.substr(i * 30, 30));
		}

		for (int _ = 0; _ < q; _++){
			int x; cin >> x;

			int P = 1;
			int res = 0;
			for (int j = 0; j < n; j++){
				res = (res + 1LL * P * f[j]) % mod;
				P = 1LL * P * x;
			}

			cout << res << "\n";
		}
	}
}

void main_program(){
	cin >> player;

	if (player == 1) encode::solve();
	else decode::solve();
}

详细

Subtask #1:

score: 0
Wrong Answer

Test #1:

score: 0
Wrong Answer
time: 8ms = 8ms + 0ms
memory: 3644kb,3648kb

input:

1
100
495528311 963488152
269613430 443544124
700489871 792354118
151890319 506569919
180452297 13229948
684464994 543841485
978085128 903812192
238355172 441140842
28061035 783291471
530823766 718942732
936853023 439421263
201361623 226633955
304644844 778868118
864860135 461524170
88300500 6959354...

output:

3000
0111001101110010000011010001011100010010110110001101111010000100111000111111010101101110000000101001011100010011000100111101101101010011110010111010111000111101000111101111000000100011001101000110101111100111000100100110101111111110010110000101010101110010101100010001010011000101100110000101111...

input:

2
100 79 3000
0111001101110010000011010001011100010010110110001101111010000100111000111111010101101110000000101001011100010011000100111101101101010011110010111010111000111101000111101111000000100011001101000110101111100111000100100110101111111110010110000101010101110010101100010001010011000101100110...

output:

-571262522
591611762
-412502711
198596713
-85883856
729397756
441107209
-741276610
312578464
-99114709
-778777743
-660975501
348704604
766976770
-720122736
584847931
683924817
341659358
-656858315
132013576
-251906953
-850943141
-351935719
704054798
549557148
-831775938
-313487985
505337521
-1984978...

result:

wrong answer wrong answer on query #1: read -571262522 but expected 310305144