제출 #1205905

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1205905		friendiks	Palindromic Partitions (CEOI17_palindromic)	C++20	0 / 100	16 ms	15936 KiB

palindromic

#ifndef LOCAL
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
#pragma GCC diagnostic ignored "-Wpedantic"
#endif

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

using namespace std;
using namespace __gnu_pbds;

auto seed = chrono::high_resolution_clock::now().time_since_epoch().count();
mt19937 rnd(52);
template<typename T>
using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
template<typename T, typename V>
using table = gp_hash_table<T, V>;

using i128 = __int128;
using ll = long long;
using ld = long double;
using uint = unsigned int;
using ull = unsigned long long;

const ll INF = 2e18;
const int inf = 2e9;
const int maxn = 1e6;
const int MOD = 1e9 + 7;
const ld pi = acos(-1);
const int P = 5167;
const int L = 26;
const ld EPS = 1e-7;

template<typename T, typename V>
void fill(T &container, V value) {
    for (auto &c: container)
        c = value;
}

#define int ll

int ps[maxn];
int backps[maxn];

string get_str(int l, int r, string&s) {
    string res;
    for (int i = l-1; i < r; ++i) res += s[i];
    return res;
}

int cnt(int l, int r, string&s) {
    int mx = 1;
    for (int len = 1; 2 * len <= r - l + 1; ++len) {
        if (get_str(l, l + len - 1, s) == get_str(r - len + 1, r, s)) {
            mx = max(mx, 2 + cnt(l + len, r - len, s));
        }
    }
    return mx;
}

int bp(int a, int n) {
    int res = 1;
    while (n) {
        if (n & 1) {
            res *= a;
            res %= MOD;
        }
        a *= a;
        a %= MOD;
        n /= 2;
    }
    return res;
}

void solve() {
    string s;
    cin >> s;
    int n = s.size();
    cout << cnt(1, n, s) << "\n";
}

signed main() {
    ps[0] = 1;
    for (int i = 1; i < maxn; ++i) ps[i] = (ps[i - 1] * P) % MOD;
    backps[maxn - 1] = bp(ps[maxn - 1], MOD - 2);
    for (int i = maxn - 1; i > 0; --i) backps[i - 1] = (backps[i] * P) % MOD;
#ifdef LOCAL
    freopen("input.txt", "r", stdin);
    freopen("output.txt", "w", stdout);
#endif
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    cout << fixed << setprecision(4);
    int t = 1;
    cin >> t;
    while (t--) solve();
    //stress();
}

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