oj.uz

Submission #538060

# Submission time Handle Problem Language Result Execution time Memory
538060 2022-03-16T04:19:24 Z skittles1412 Necklace (Subtask 1-3) (BOI19_necklace1) C++17
45 / 85
 1500 ms 448 KB 
#include "bits/extc++.h"

using namespace std;

template <typename T>
void dbgh(const T& t) {
	cerr << t << endl;
}

template <typename T, typename... U>
void dbgh(const T& t, const U&... u) {
	cerr << t << " | ";
	dbgh(u...);
}

#ifdef DEBUG
#define dbg(...)                                           \
	cerr << "L" << __LINE__ << " [" << #__VA_ARGS__ << "]" \
		 << ": ";                                          \
	dbgh(__VA_ARGS__)
#else
#define cerr   \
	if (false) \
	cerr
#define dbg(...)
#endif

#define endl "\n"
#define long int64_t
#define sz(x) int((x).size())

namespace s1 {

bool eqr(string s, const string &t) {
	for (int i = 0; i < sz(s); i++) {
		if (s == t) {
			return true;
		}
		rotate(s.begin(), s.begin() + 1, s.end());
	}
	return false;
}

bool eq(string s, const string &t) {
	if (eqr(s, t)) {
		return true;
	}
	reverse(begin(s), end(s));
	return eqr(s, t);
}

void solve(const string &s, const string &t) {
	int n = sz(s), m = sz(t);
	array<int, 3> ans {};
	for (int i = 1; i <= n; i *= 2) {
		for (int j = 0; j + i <= n; j++) {
			for (int k = 0; k + i <= m; k++) {
				if (eq(s.substr(j, i), t.substr(k, i))) {
					ans = {i, j, k};
				}
			}
		}
	}
	auto [a, b, c] = ans;
	cout << a << endl;
	cout << b << " " << c << endl;
}

}

constexpr long bpow(long base, long exp, long mod) {
	long ans = 1;
	while (exp) {
		if (exp & 1) {
			ans = (ans * base) % mod;
		}
		exp >>= 1;
		base = (base * base) % mod;
	}
	return ans;
}

constexpr long inv(long x, long mod) {
	return bpow(x, mod - 2, mod);
}

template <long base, long mod>
struct Pow {
	static constexpr int maxn = 3e3 + 5;
	long arr[maxn];

	constexpr Pow() : arr() {
		arr[0] = 1;
		for (int i = 1; i < maxn; i++) {
			arr[i] = (arr[i - 1] * base) % mod;
		}
	}

	long operator[](int i) const {
		return arr[i];
	}
};

template <long base, long mod>
struct Hasher {
	static constexpr long ibase = inv(base, mod);
	static constexpr Pow<base, mod> pow {};
	static constexpr Pow<ibase, mod> ipow {};
	vector<long> psum;

	explicit Hasher(const string& s) : psum(sz(s) + 1) {
		for (int i = 0; i < sz(s); i++) {
			psum[i + 1] = (psum[i] + (s[i] - 'a' + 1) * pow[i]) % mod;
		}
	}

	long hash(int l, int r) const {
		return (psum[r] - psum[l] + mod) * ipow[l] % mod;
	}

	long merge(int len, long a, long b) const {
		return (a + b * pow[len]) % mod;
	}

	long rot(int len, long h) const {
		long x = h % base;
		return ((h - x + mod) * ibase + x * pow[len - 1]) % mod;
	}
};

const long base = 31, base2 = 29, mod = 1e9 + 7;

tuple<int, int, int> solve(const string& s, const string& t) {
	Hasher<base, mod> hs(s), ht(t);
	Hasher<base2, mod> hs2(s), ht2(t);
	int n = sz(s), m = sz(t);
	for (int i = n; i >= 1; i--) {
		map<pair<long, long>, int> cur, cur2;
		for (int j = 0; j + i <= m; j++) {
			cur[{ht.hash(j, j + i), ht2.hash(j, j + i)}] = j;
		}
		for (int j = 0; j + i <= n; j++) {
			for (int k = 0; k < i; k++) {
				long x = hs.merge(i - k, hs.hash(j + k, j + i), hs.hash(j, j + k));
				long x2 = hs2.merge(i - k, hs2.hash(j + k, j + i), hs2.hash(j, j + k));
				auto it = cur.find({x, x2});
				if (it != cur.end()) {
					return {i, j, it->second};
				}
			}
		}
	}
	assert(false);
}

void solve() {
	{
		Hasher<base, mod> tmp("bcbcccb"), tmp1("cbcccbb");
		long x = tmp.hash(0, 7);
		for (int i = 0; i < 7; i++) {
			x = tmp.rot(7, x);
			dbg(x);
		}
		dbg(tmp1.hash(0, 7));
	}
	string s, t;
	cin >> s >> t;
	if (max(sz(s), sz(t)) > 400) {
		s1::solve(s, t);
		return;
	}
	auto [x, a, b] = solve(s, t);
	reverse(begin(s), end(s));
	auto [x1, a1, b1] = solve(s, t);
	dbg(x, a, b, x1, a1, b1);
	if (x1 > x) {
		x = x1;
		a = sz(s) - a1 - x;
		b = b1;
	}
	cout << x << endl;
	cout << a << " " << b << endl;
}

int main() {
	cin.tie(nullptr);
	ios_base::sync_with_stdio(false);
	cin.exceptions(ios::failbit);
	solve();
}

Subtask #1
25.0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 1 ms 212 KB Output is correct
3 Correct 5 ms 212 KB Output is correct
4 Correct 10 ms 320 KB Output is correct
5 Correct 16 ms 324 KB Output is correct

Subtask #2
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 1 ms 212 KB Output is correct
3 Correct 5 ms 212 KB Output is correct
4 Correct 10 ms 320 KB Output is correct
5 Correct 16 ms 324 KB Output is correct
6 Correct 41 ms 212 KB Output is correct
7 Correct 108 ms 316 KB Output is correct
8 Correct 492 ms 324 KB Output is correct
9 Correct 744 ms 328 KB Output is correct
10 Correct 1046 ms 448 KB Output is correct
11 Correct 1111 ms 320 KB Output is correct
12 Correct 751 ms 324 KB Output is correct

Subtask #3
0.0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 1 ms 212 KB Output is correct
3 Correct 5 ms 212 KB Output is correct
4 Correct 10 ms 320 KB Output is correct
5 Correct 16 ms 324 KB Output is correct
6 Correct 41 ms 212 KB Output is correct
7 Correct 108 ms 316 KB Output is correct
8 Correct 492 ms 324 KB Output is correct
9 Correct 744 ms 328 KB Output is correct
10 Correct 1046 ms 448 KB Output is correct
11 Correct 1111 ms 320 KB Output is correct
12 Correct 751 ms 324 KB Output is correct
13 Execution timed out 1585 ms 212 KB Time limit exceeded
14 Halted 0 ms 0 KB -