oj.uz

Submission #153079

# Submission time Handle Problem Language Result Execution time Memory
153079 2019-09-12T09:12:13 Z admin Round words (IZhO13_rowords) C++14
100 / 100
 163 ms 504 KB 
#include <bits/stdc++.h>

#define get(arr, x) (((arr[x >> 6] >> (x & 63)) & 1) == 1)
#define set(arr, x) (arr[x >> 6] |= 1llu << (x & 63))
using ulint = unsigned long long;

int lcs(std::string A, std::string B) {
  int N = A.size(), M = B.size();
  int sz = (M >> 6) + 1;

  std::vector<ulint> S[26];
  for(int c = 0; c < 26; c++) S[c].resize(sz);
  for(int j = 0; j < M; j++) set(S[B[j] - 'a'], j);
  
  std::vector<ulint> row(sz);
  for(int j = 0; j < M; j++) if(A[0] == B[j]) { set(row, j); break; }

  for(int i = 1; i < N; i++) {
    ulint shl_carry = 1;
    ulint minus_carry = 0;
    
    for(int k = 0; k < sz; k++) {
      // Compute k-th block of x == S[A[i]] OR M[i-1]
      ulint x_k = S[A[i] - 'a'][k] | row[k];

      // Compute k-th block of "(M[i-1] << 1) | 1"
      ulint term_1 = (row[k] << 1) | shl_carry;
      shl_carry = row[k] >> 63;

      // Compute k-th block of "x - ((M[i-1] << 1) | 1)"
      auto sub_carry = [](ulint &x, ulint y){
        ulint tmp = x;
        return (x = tmp - y) > tmp;
      };
      ulint term_2 = x_k;
      minus_carry = sub_carry(term_2, minus_carry);
      minus_carry += sub_carry(term_2, term_1);
      
      row[k] = x_k & (x_k ^ term_2);
    }

    row[M >> 6] &= (1llu << (M & 63)) - 1;
  }

  int ret = 0;
  for(int j = 0; j < M; j++) if(get(row, j)) ret += 1;
  return ret;
}

int main() {
  std::string a, b;
  std::cin >> a >> b;

  int ans = 0;
  
  for(int rep = 0; rep < 2; rep++) {
    for(int i = 0; i < int(b.size()); i++) {
      ans = std::max(ans, lcs(a, b));
      std::rotate(b.begin(), b.begin() + 1, b.end());
    }
    std::reverse(b.begin(), b.end());
  }
  std::cout << ans << std::endl;
  return 0;
}

Subtask #1
100.0 / 100.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 376 KB Output is correct
2 Correct 3 ms 376 KB Output is correct
3 Correct 2 ms 256 KB Output is correct
4 Correct 2 ms 256 KB Output is correct
5 Correct 3 ms 256 KB Output is correct
6 Correct 5 ms 376 KB Output is correct
7 Correct 115 ms 376 KB Output is correct
8 Correct 118 ms 376 KB Output is correct
9 Correct 115 ms 376 KB Output is correct
10 Correct 111 ms 256 KB Output is correct
11 Correct 120 ms 364 KB Output is correct
12 Correct 146 ms 504 KB Output is correct
13 Correct 145 ms 504 KB Output is correct
14 Correct 125 ms 376 KB Output is correct
15 Correct 163 ms 376 KB Output is correct
16 Correct 121 ms 256 KB Output is correct
17 Correct 54 ms 368 KB Output is correct
18 Correct 120 ms 376 KB Output is correct
19 Correct 111 ms 364 KB Output is correct
20 Correct 109 ms 256 KB Output is correct
21 Correct 9 ms 256 KB Output is correct
22 Correct 17 ms 256 KB Output is correct
23 Correct 29 ms 256 KB Output is correct
24 Correct 31 ms 400 KB Output is correct
25 Correct 51 ms 376 KB Output is correct