Submission #252186

#	Time	Username	Problem	Language	Result	Execution time	Memory
252186		Haunted_Cpp	Palindromic Partitions (CEOI17_palindromic)	C++17	60 / 100	793 ms	99136 KiB

palindromic

/**
 * author: Haunted_Cpp
**/

#include <bits/stdc++.h>
using namespace std;

template<typename T> ostream &operator << (ostream &os, const vector<T> &v) { os << '{'; string sep; for (const auto &x : v) os << sep << x, sep = ", "; return os << '}'; }
template<typename T, size_t size> ostream &operator << (ostream &os, const array<T, size> &arr) { os << '{'; string sep; for (const auto &x : arr) os << sep << x, sep = ", "; return os << '}'; }
template<typename A, typename B> ostream &operator << (ostream &os, const pair<A, B> &p) { return os << '(' << p.first << ", " << p.second << ')'; }
 
void debug_out() { cerr << endl; }
template<typename Head, typename... Tail> void debug_out(Head H, Tail... T) { cerr << ' ' << H; debug_out(T...); }
 
#ifdef LOCAL
#define debug(...) cerr << "(" << #__VA_ARGS__ << "):", debug_out(__VA_ARGS__)
#else
#define debug(...) 47
#endif

const int N = 1e4 + 50;

int dp[N], n;
string w;

vector<int> calc_z(string cur) {
  const int T = (int) cur.size();
  vector<int> z(T);
  z[0] = 0;
  int L = 0, R = 0;
  for (int i = 1; i < T; i++) {
    z[i] = (i <= R ? min(z[i - L], R - i + 1) : 0);
    while(i + z[i] < T && cur[i + z[i]] == cur[z[i]]) ++z[i]; 
    if (i + z[i] > R) {
      L = i;
      R = i + z[i] - 1;
    } 
  }
  return z;
}

int solve(int l) {
  int r = n - l - 1;
  if (l > r) return 0;
  int &res = dp[l];
  if (~res) return res;
  res = 1;
  int size = r - l + 1;
  vector<int> z = calc_z(w.substr(l, size));
  for (int i = 0; i < (int) z.size(); i++) {
    if (i + z[i] >= size) {
      res = max(res, 2 + solve(l + z[i]));
    }
  }
  return res;
}

int main() {
  ios::sync_with_stdio(0);
  cin.tie(0);
  int t;
  cin >> t;
  while(t--) {
    cin >> w;
    n = (int) w.size();
    for (int i = 0; i < n; i++) dp[i] = -1;
    cout << solve(0) << '\n';
  }
  return 0;
}

• Subtask 1: 15 / 15
• Subtask 2: 20 / 20
• Subtask 3: 25 / 25
• Subtask 4: 0 / 40