Submission #657059

# Submission time Handle Problem Language Result Execution time Memory
657059 2022-11-08T19:43:13 Z bicsi Necklace (Subtask 1-3) (BOI19_necklace1) C++14
45 / 85
53 ms 344 KB
#include <bits/stdc++.h>

using namespace std;
using ld = long double;

using C = complex<ld>;
const ld EPS = 1e-9;

int main() {
  string s, t; cin >> s >> t;

  mt19937_64 rng(52);
  vector<C> rnd(256);
  for (int i = 0; i < 256; ++i) {
    ld real = 1.0L * rng() / rng.max();
    ld imag = 1.0L * rng() / rng.max();
    rnd[i] = C(real, imag);
    rnd[i] /= abs(rnd[i]);
  }

  auto cmp = [&](const pair<C, int>& aa, const pair<C, int>& bb) {
    auto& a = aa.first;
    auto& b = bb.first;
    if (abs(a.real() - b.real()) / 
        max(abs(a.real()), abs(b.real())) > EPS) 
      return a.real() < b.real();
    if (abs(a.imag() - b.imag()) / 
        max(abs(a.imag()), abs(b.imag())) > EPS) 
      return a.imag() < b.imag();
    return false;
  };
  
  vector<pair<C, int>> vs, vt;
  auto check = [&](int len) {
    C eps = polar(1.0, 2.0 * M_PI / len);
    pair<int, int> ans = {-1, -1};
    for (int rev = 0; rev < 2; ++rev) {
      vs.clear(); vt.clear();
      for (int it = 0; it < 2; ++it) {
        C h = 0;
        for (int i = 0; i < (int)s.size(); ++i) {
          h = (h + rnd[s[i]]) * eps;
          if (i >= len - 1) {
            C now = pow(h, len);
            vs.emplace_back(now, i - len + 1);
            h -= rnd[s[i - len + 1]];
          }
        }
        swap(s, t); swap(vs, vt);
      }
      sort(vs.begin(), vs.end(), cmp);
      sort(vt.begin(), vt.end(), cmp);
      for (int i = 0, j = 0; i < (int)vs.size(); ++i) {
        while (j < vt.size() && !cmp(vs[i], vt[j])) {
          if (!cmp(vt[j], vs[i])) {
            ans.first = vs[i].second;
            ans.second = vt[j].second;
            if (rev) ans.first = s.size() - ans.first - len;
          }
          ++j;
        }
      }
      reverse(s.begin(), s.end());
    }
    return ans;
  };

  int ans = 0, ps = -1, pt = -1;
  for (int i = (int)s.size(); i >= 0; --i) {
    auto [a, b] = check(i);
    if (a >= 0) {
      ans = i, ps = a, pt = b;
      break;
    }
  }
  cout << ans << endl << ps << " " << pt << endl;

  return 0;
}

Compilation message

necklace.cpp: In lambda function:
necklace.cpp:54:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<std::complex<long double>, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   54 |         while (j < vt.size() && !cmp(vs[i], vt[j])) {
      |                ~~^~~~~~~~~~~
necklace.cpp: In function 'int main()':
necklace.cpp:70:10: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   70 |     auto [a, b] = check(i);
      |          ^
# 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 2 ms 212 KB Output is correct
4 Correct 2 ms 212 KB Output is correct
5 Correct 3 ms 300 KB Output is correct
# 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 2 ms 212 KB Output is correct
4 Correct 2 ms 212 KB Output is correct
5 Correct 3 ms 300 KB Output is correct
6 Correct 4 ms 212 KB Output is correct
7 Correct 3 ms 212 KB Output is correct
8 Correct 24 ms 340 KB Output is correct
9 Correct 32 ms 340 KB Output is correct
10 Correct 44 ms 344 KB Output is correct
11 Correct 53 ms 344 KB Output is correct
12 Correct 32 ms 344 KB Output is correct
# 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 2 ms 212 KB Output is correct
4 Correct 2 ms 212 KB Output is correct
5 Correct 3 ms 300 KB Output is correct
6 Correct 4 ms 212 KB Output is correct
7 Correct 3 ms 212 KB Output is correct
8 Correct 24 ms 340 KB Output is correct
9 Correct 32 ms 340 KB Output is correct
10 Correct 44 ms 344 KB Output is correct
11 Correct 53 ms 344 KB Output is correct
12 Correct 32 ms 344 KB Output is correct
13 Incorrect 1 ms 212 KB Output isn't correct
14 Halted 0 ms 0 KB -