oj.uz

Submission #133147

# Submission time Handle Problem Language Result Execution time Memory
133147 2019-07-20T07:59:09 Z E869120 Necklace (Subtask 1-3) (BOI19_necklace1) C++14
85 / 85
 507 ms 1916 KB 
#include <iostream>
#include <string>
#include <algorithm>
#include <vector>
#include <tuple>
using namespace std;

const int BACKET = 55;

int N, M, pa_long[60][3009], pa_short[60][3009];
int EA[6009], EB[6009];
int prevs[6009], dp[6009];

tuple<int, int, int> solve(string S, string T) {
	N = S.size(); M = T.size();
	for (int i = 0; i < M; i++) prevs[i] = 0;
	for (int i = 0; i < N; i++) {
		for (int j = 0; j < M; j++) {
			dp[j] = 0;
			if (S[i] == T[j]) dp[j] = 1;
			if (i >= 1 && j >= 1 && S[i] == T[j]) {
				dp[j] = prevs[j - 1] + 1;
			}
		}
		for (int j = 0; j < M; j++) prevs[j] = dp[j];
		if (i % BACKET == 0) {
			for (int j = 0; j < M; j++) pa_long[i / BACKET][j] = prevs[j];
		}
	}

	int maxn = 0; pair<int, int> maxid = make_pair(-1, -1);
	for (int i = 0; i <= M; i++) prevs[i] = 0;

	for (int i = N; i >= 0; i--) {
		// Step 1 : 更新処理 (pa)
		if (i == N || (i - 1) % BACKET == BACKET - 1) {
			int c = ((i - 1) / BACKET) * BACKET;
			for (int j = 0; j < M; j++) pa_short[0][j] = pa_long[c / BACKET][j];

			for (int j = 1; j < BACKET; j++) {
				if (c + j >= N) break;
				for (int k = 0; k < M; k++) {
					pa_short[j][k] = 0;
					if (S[c + j] == T[k]) pa_short[j][k] = 1;
					if (c + j >= 1 && k >= 1 && S[c + j] == T[k]) {
						pa_short[j][k] = pa_short[j - 1][k - 1] + 1;
					}
				}
			}
		}

		// Step 2 : 更新処理 (pb)
		if (i < N) {
			for (int j = 0; j < M; j++) {
				dp[j] = 0;
				if (S[i] == T[j]) dp[j] = 1;
				if (i < N - 1 && j < M - 1 && S[i] == T[j]) {
					dp[j] = prevs[j + 1] + 1;
				}
			}
			for (int j = 0; j < M; j++) { prevs[j] = dp[j]; }
		}

		// Step 2 : S における境界が i の場合の計算
		vector<int> A, B;
		for (int j = 0; j < M; j++) {
			if (i == N) A.push_back(0);
			else A.push_back(prevs[j]);
		}
		for (int j = 0; j < M; j++) {
			if (i == 0) B.push_back(0);
			else B.push_back(pa_short[(i - 1) % BACKET][j]);
		}
		for (int j = 0; j <= 6000; j++) { EA[j] = (1 << 29); EB[j] = -(1 << 29); }
		for (int j = 0; j < N; j++) {
			EA[A[j] + j] = min(EA[A[j] + j], j);
			EB[max(0, -B[j] + j + 1)] = max(EB[max(0, -B[j] + j + 1)], j);
		}
		
		// ret1 には条件を満たす最も左のインデックスを記録
		int ret1 = -(1 << 29);
		for (int j = 0; j <= 6000; j++) {
			ret1 = max(ret1, EB[j]);
			int cr = ret1, cl = EA[j];
			if (maxn < cr - cl + 1) {
				maxn = cr - cl + 1;
				maxid = make_pair(i - B[cr], cl);
			}
		}
	}
	return make_tuple(maxn, maxid.first, maxid.second);
}

int main() {
	string A1, B1, B2; cin >> A1 >> B1; B2 = B1; reverse(B2.begin(), B2.end());
	tuple<int, int, int> v1 = solve(A1, B1);
	tuple<int, int, int> v2 = solve(A1, B2);

	cout << max(get<0>(v1), get<0>(v2)) << endl;
	if (get<0>(v1) > get<0>(v2)) cout << get<1>(v1) << " " << get<2>(v1) << endl;
	if (get<0>(v1) <= get<0>(v2)) cout << get<1>(v2) << " " << M - (get<2>(v2) + get<0>(v2)) << endl;
	return 0;
}

Subtask #1
25.0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 632 KB Output is correct
2 Correct 6 ms 632 KB Output is correct
3 Correct 5 ms 632 KB Output is correct
4 Correct 6 ms 632 KB Output is correct
5 Correct 6 ms 632 KB Output is correct

Subtask #2
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 632 KB Output is correct
2 Correct 6 ms 632 KB Output is correct
3 Correct 5 ms 632 KB Output is correct
4 Correct 6 ms 632 KB Output is correct
5 Correct 6 ms 632 KB Output is correct
6 Correct 23 ms 776 KB Output is correct
7 Correct 23 ms 760 KB Output is correct
8 Correct 21 ms 760 KB Output is correct
9 Correct 21 ms 760 KB Output is correct
10 Correct 22 ms 760 KB Output is correct
11 Correct 22 ms 732 KB Output is correct
12 Correct 21 ms 760 KB Output is correct

Subtask #3
40.0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 632 KB Output is correct
2 Correct 6 ms 632 KB Output is correct
3 Correct 5 ms 632 KB Output is correct
4 Correct 6 ms 632 KB Output is correct
5 Correct 6 ms 632 KB Output is correct
6 Correct 23 ms 776 KB Output is correct
7 Correct 23 ms 760 KB Output is correct
8 Correct 21 ms 760 KB Output is correct
9 Correct 21 ms 760 KB Output is correct
10 Correct 22 ms 760 KB Output is correct
11 Correct 22 ms 732 KB Output is correct
12 Correct 21 ms 760 KB Output is correct
13 Correct 507 ms 1820 KB Output is correct
14 Correct 472 ms 1784 KB Output is correct
15 Correct 490 ms 1784 KB Output is correct
16 Correct 488 ms 1912 KB Output is correct
17 Correct 482 ms 1912 KB Output is correct
18 Correct 491 ms 1916 KB Output is correct
19 Correct 472 ms 1812 KB Output is correct
20 Correct 471 ms 1912 KB Output is correct
21 Correct 481 ms 1784 KB Output is correct