Submission #1082107

# Submission time Handle Problem Language Result Execution time Memory
1082107 2024-08-30T17:17:25 Z juicy Palinilap (COI16_palinilap) C++17
54 / 100
31 ms 24664 KB
#include <bits/stdc++.h>
 
using namespace std;
 
#ifdef LOCAL
#include "debug.h"
#else
#define debug(...) 42
#endif
 
using ull = unsigned long long;
 
const int N = 1e5 + 5, B = 33;
 
int n;
int cnt[N];
long long f[N];
array<long long, 26> c[N];
string s;
ull h[N], rh[N], pw[N];
 
ull qry(int l, int r, ull *h) {
  return h[r] - h[l - 1] * pw[r - l + 1];
}
 
int find(int s, int e) {
  if (s < 1 || e > n) {
    return 0;
  }
  int l = 0, r = min(s, n - e + 1), res = 0;
  while (l <= r) {
    int m = (l + r) / 2;
    if (qry(s - m + 1, s, h) == qry(n - e - m + 2, n - e + 1, rh)) {
      res = m;
      l = m + 1;
    } else {
      r = m - 1;
    }
  }
  return res;
}
 
template<class T>
void upd(int s, int e, int x, T *f) {
  f[s] += x;
  f[e + 1] -= x; 
}
 
signed main() {
  ios::sync_with_stdio(false); cin.tie(nullptr);
 
  cin >> s;
  n = s.size();
  pw[0] = 1;
  for (int i = 0; i < n; ++i) {
    pw[i + 1] = pw[i] * B;
    h[i + 1] = h[i] * B + s[i] - 'a' + 1;
  }
  for (int i = n - 1; i >= 0; --i) {
    rh[i + 1] = rh[i + 2] * B + s[i] - 'a' + 1;
  }
  reverse(rh + 1, rh + n + 1);
  long long res = 0;
  for (int i = 1; i < n; ++i) {
    int l = find(i, i + 1);
    res += l;
    int L = i - l + 1, R = i + l;
    if (l > 0) {
      upd(i + 1, i + l, 1, cnt);
      upd(i + 1, i + l, -R - 1, f);
      upd(i - l + 1, i, -1, cnt);
      upd(i - l + 1, i, L - 1, f);
    }
    if (1 < L && R < n) {
      int l = find(L - 2, R + 2);
      c[L - 1][s[R] - 'a'] += l + 1;
      c[R + 1][s[L - 2] - 'a'] += l + 1;
    }
  }
  for (int i = 1; i <= n; ++i) {
    int l = find(i - 1, i + 1) + 1;
    res += l;
    int L = i - l + 1, R = i + l - 1;
    if (l > 1) {
      upd(L, i - 1, -1, cnt);
      upd(L, i - 1, L - 1, f);
      upd(i + 1, R, 1, cnt);
      upd(i + 1, R, -R - 1, f);
    }
    if (1 < L && R < n) {
      int l = find(L - 2, R + 2);
      c[L - 1][s[R] - 'a'] += l + 1;
      c[R + 1][s[L - 2] - 'a'] += l + 1;
    }
  }
  long long ma = 0;
  for (int i = 1; i <= n; ++i) {
    cnt[i] += cnt[i - 1];
    f[i] += f[i - 1];
    long long delta = (long long) cnt[i] * i + f[i];
    for (int j = 0; j < 26; ++j) {
      ma = max(ma, delta + c[i][j]);
    }
  }
  cout << res + ma;
  return 0;
}
# Verdict Execution time Memory Grader output
1 Correct 1 ms 4444 KB Output is correct
2 Correct 1 ms 4444 KB Output is correct
3 Correct 1 ms 4444 KB Output is correct
4 Correct 1 ms 4444 KB Output is correct
5 Correct 1 ms 4444 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 4700 KB Output is correct
2 Correct 1 ms 4700 KB Output is correct
3 Correct 1 ms 4700 KB Output is correct
4 Correct 2 ms 4444 KB Output is correct
5 Correct 2 ms 4700 KB Output is correct
6 Correct 2 ms 4696 KB Output is correct
7 Correct 2 ms 4700 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 26 ms 24412 KB Output is correct
2 Correct 17 ms 24408 KB Output is correct
3 Correct 19 ms 24412 KB Output is correct
4 Correct 26 ms 24420 KB Output is correct
5 Correct 27 ms 24400 KB Output is correct
6 Correct 25 ms 24412 KB Output is correct
7 Correct 27 ms 24408 KB Output is correct
8 Correct 14 ms 8024 KB Output is correct
9 Correct 28 ms 24456 KB Output is correct
10 Correct 31 ms 24412 KB Output is correct
11 Correct 19 ms 24408 KB Output is correct
12 Correct 29 ms 24532 KB Output is correct
13 Correct 24 ms 24552 KB Output is correct
14 Correct 26 ms 24412 KB Output is correct
15 Correct 25 ms 24412 KB Output is correct
16 Correct 26 ms 24664 KB Output is correct
17 Correct 25 ms 24412 KB Output is correct
18 Incorrect 26 ms 24408 KB Output isn't correct
19 Halted 0 ms 0 KB -