제출 #46479

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
46479		RockyB	Palindromic Partitions (CEOI17_palindromic)	C++17	60 / 100	10023 ms	21116 KiB

palindromic

/// In The Name Of God

#pragma GCC optimize("Ofast")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")

#include <bits/stdc++.h>

#define f first
#define s second

#define pb push_back
#define pp pop_back
#define mp make_pair

#define sz(x) (int)x.size()
#define sqr(x) ((x) * 1ll * (x))
#define all(x) x.begin(), x.end()

#define Kazakhstan ios_base :: sync_with_stdio(0), cin.tie(0), cout.tie(0);

#define nl '\n'
#define ioi exit(0);

typedef long long ll;
typedef long double ld;
typedef unsigned long long ull;

const int N = (int)1e6 + 7;
const int inf = (int)1e9 + 7;
const int mod = (int)1e9 + 7;
const ll linf = (ll)1e18 + 7;

const int dx[] = {-1, 0, 1, 0, 1, -1, -1, 1};
const int dy[] = {0, 1, 0, -1, 1, -1, 1, -1};

using namespace std;

int n;
char s[N];
int dp[N];



const int p1 = 997;

struct hs {
	ull h[N], dg[N];
	void init() {
		dg[0] = 1;
		for (int i = 0; i <= n; i++) {
			dg[i + 1] = dg[i] * p1;
			if (i) h[i + 1] = h[i] * p1 + s[i];
		}
	}
	ull get(int l, int r) {
		return h[r + 1] - h[l] * dg[r - l + 1];
	}
} t;

bool check(int l1, int l2, int len) {
	return t.get(l1, l1 + len - 1) == t.get(l2, l2 + len - 1);
	for (int i = 0; i < len; i++) {
		if (s[i + l1] != s[i + l2]) return 0;
	}
	return 1;
}
void solve() {
	cin >> (s + 1);
	n = strlen(s + 1);
	memset(dp, -0x3f, sizeof(dp));
	dp[0] = 0;
	t.init();
	int go = (n + 1) >> 1;
	for (int i = 1; i <= go; i++) {
		int total = 0, len = 0;
		for (int j = i; j >= 1 && total <= 200 && ++len <= 10000; j--) {
			if (check(j, n - i + 1, i - j + 1)) {
				++total;
				dp[i] = max(dp[i], dp[j - 1] + 1 + (j != n - i + 1));
			}
		}
	}
	int ans = 0;
	for (int i = 1; i <= n; i++) {
		if (i <= n / 2) ans = max(ans, dp[i]);
		int l = i, r = n - i + 1;
		if (l <= r) {
			ans = max(ans, dp[l - 1] + 1);
		}
	}
	cout << ans << nl;
}
int main() {
	#ifdef IOI2018
		freopen ("in.txt", "r", stdin);
	#endif
	Kazakhstan
	int t = 1;
	cin >> t;
	while (t--) {
		solve();
	}
	ioi
}

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