oj.uz

Submission #657102

# Submission time Handle Problem Language Result Execution time Memory
657102 2022-11-08T21:33:02 Z bicsi Necklace (Subtask 1-3) (BOI19_necklace1) C++14
85 / 85
 359 ms 636 KB 
#include <bits/stdc++.h>

using namespace std;
using ld = long double;
const ld EPS = 1e-10;

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

  mt19937_64 rng(52);
  vector<complex<ld>> 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] = {real, imag};
  }
  
  vector<pair<ld, int>> vs, vt;
  auto check = [&](int len) {
    complex<ld> eps = polar(1.0L, 2.0L * 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) {
        complex<ld> h = 0;
        for (int i = 0; i < (int)s.size(); ++i) {
          h = (h + rnd[s[i]]) * eps;
          if (i >= len - 1) {
            vs.emplace_back(norm(h), i - len + 1);
            h -= rnd[s[i - len + 1]];
          }
        }
        swap(s, t); swap(vs, vt);
      }
      sort(vs.begin(), vs.end());
      sort(vt.begin(), vt.end());
      for (int i = 0, j = 0; i < (int)vs.size(); ++i) {
        while (j < vt.size() && vs[i].first + EPS > vt[j].first) {
          if (abs(vt[j].first - vs[i].first) < EPS) {
            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;
  int bound = 1;
  while (check(bound).first >= 0) bound *= 2;
  for (int i = bound; i >= bound/2; --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:38:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<long double, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   38 |         while (j < vt.size() && vs[i].first + EPS > vt[j].first) {
      |                ~~^~~~~~~~~~~
necklace.cpp: In function 'int main()':
necklace.cpp:56:10: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   56 |     auto [a, b] = check(i);
      |          ^

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 1 ms 212 KB Output is correct
4 Correct 1 ms 212 KB Output is correct
5 Correct 1 ms 212 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 1 ms 212 KB Output is correct
4 Correct 1 ms 212 KB Output is correct
5 Correct 1 ms 212 KB Output is correct
6 Correct 4 ms 340 KB Output is correct
7 Correct 5 ms 340 KB Output is correct
8 Correct 3 ms 340 KB Output is correct
9 Correct 4 ms 340 KB Output is correct
10 Correct 9 ms 340 KB Output is correct
11 Correct 6 ms 340 KB Output is correct
12 Correct 4 ms 340 KB Output is correct

Subtask #3
40.0 / 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 1 ms 212 KB Output is correct
4 Correct 1 ms 212 KB Output is correct
5 Correct 1 ms 212 KB Output is correct
6 Correct 4 ms 340 KB Output is correct
7 Correct 5 ms 340 KB Output is correct
8 Correct 3 ms 340 KB Output is correct
9 Correct 4 ms 340 KB Output is correct
10 Correct 9 ms 340 KB Output is correct
11 Correct 6 ms 340 KB Output is correct
12 Correct 4 ms 340 KB Output is correct
13 Correct 185 ms 636 KB Output is correct
14 Correct 176 ms 624 KB Output is correct
15 Correct 114 ms 620 KB Output is correct
16 Correct 130 ms 624 KB Output is correct
17 Correct 50 ms 624 KB Output is correct
18 Correct 47 ms 624 KB Output is correct
19 Correct 350 ms 624 KB Output is correct
20 Correct 247 ms 624 KB Output is correct
21 Correct 359 ms 624 KB Output is correct