Submission #1002692

#	Time	Username	Problem	Language	Result	Execution time	Memory
1002692		aykhn	Dabbeh (INOI20_dabbeh)	C++17	25 / 100	624 ms	171144 KiB

Main

#include <bits/stdc++.h>
 
using namespace std;
 
#define int long long
#define inf 0x3F3F3F3F3F3F3F3F
 
const int MXN = 1e6 + 5;
const int LOG = 20;
const int mod = 1e9 + 7;
const int base = 9128398;
 
int ph[2][MXN], p[MXN], invp[MXN];
 
int mult(int a, int b)
{
  return (a * b) % mod;
}
 
int add(int a, int b)
{
  return (a + b) % mod;
}
 
int pw(int a, int b, int c)
{
  a %= c;
  int res = 1;
  while (b)
  {
    if (b & 1) res = mult(res, a);
    a = mult(a, a);
    b >>= 1;
  }
  return res;
}
 
int get_hash(int l, int r, int id)
{
  return mult(add(ph[id][r], mod - ph[id][l - 1]), invp[l]);
}
 
void _HASH(string &s, int id)
{
  int n = (int)s.length() - 1;
  ph[id][0] = 0;
  for (int i = 1; i <= n; i++) ph[id][i] = add(ph[id][i - 1], mult(p[i], s[i] - 'a' + 1));
}
 
array<int, 2> st[MXN << 2];
int par[LOG][MXN];
void make(int l, int r, int x, int ind, int val)
{
  if (l == r)
  {
    st[x] = {val, ind};
    return;
  }
  int mid = (l + r) >> 1;
  if (ind <= mid)  make(l, mid, 2*x, ind, val);
  else make(mid + 1, r, 2*x + 1, ind, val);
  st[x] = max(st[2*x], st[2*x + 1]);
}
array<int, 2> get(int l, int r, int x, int lx, int rx)
{
  if (l > rx || r < lx) return {0, 0};
  if (l >= lx && r <= rx) return st[x];
  int mid = (l + r) >> 1;
  return max(get(l, mid, 2*x, lx, rx), get(mid + 1, r, 2*x + 1, lx, rx));
}
 
int L, n, k;
string t[MXN], s;
set<int> mp[MXN];
int nxt[MXN];
 
signed main()
{
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  p[0] = 1;
  for (int i = 1; i < MXN; i++) p[i] = mult(p[i - 1], base);
  for (int i = 0; i < MXN; i++) invp[i] = pw(p[i], mod - 2, mod);
  cin >> n >> k;
  for (int i = 0; i < n; i++) cin >> t[i];
  cin >> s;
  L = s.length();
  s = "#" + s;
  _HASH(s, 0);
  for (int i = 0; i < n; i++)
  {
    t[i] = "#" + t[i];
    _HASH(t[i], 1);
    for (int j = 1; j < t[i].length(); j++) mp[j].insert(get_hash(1, j, 1));
  }
  for (int i = 1; i <= L; i++)
  {
    if (mp[1].find(get_hash(i, i, 0)) == mp[1].end()) nxt[i] = 0;
    else
    {
      int l = i, r = L;
      while (l < r)
      {
        int mid = (l + r + 1) >> 1;
        if (mp[mid - i + 1].find(get_hash(i, mid, 0)) != mp[mid - i + 1].end()) l = mid;
        else r = mid - 1;
      }
      nxt[i] = l + 1;
    }
  }
  for (int i = 1; i <= L; i++) if (nxt[i]) make(1, L, 1, i, nxt[i]);
  for (int i = 1; i <= L; i++)
  {
    array<int, 2> j = get(1, L, 1, i, nxt[i]);
    if (j[0] > nxt[i]) 
    {
      par[0][i] = j[1];
    }
  }
  for (int i = 1; i < LOG; i++) for (int j = 1; j <= L; j++) par[i][j] = par[i - 1][par[i - 1][j]];
  while (k--)
  {
    int l, r, res = 0;
    cin >> l >> r;
    l++;
    if (nxt[l] > r) 
    {
      cout << 1 << '\n';
      continue;
    }
    for (int i = LOG - 1; i >= 0; i--)
    {
      if (!par[i][l] || nxt[par[i][l]] > r) continue;
      l = par[i][l];
      res |= (1LL << i);
    }
    if (nxt[par[0][l]] > r) cout << res + 2 << '\n';
    else cout << -1 << '\n';
  }
}

Compilation message (stderr)

Main.cpp: In function 'int main()':
Main.cpp:94:23: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   94 |     for (int j = 1; j < t[i].length(); j++) mp[j].insert(get_hash(1, j, 1));
      |                     ~~^~~~~~~~~~~~~~~

• Subtask 1: 25 / 25
• Subtask 2: 0 / 25
• Subtask 3: 0 / 50