Submission #94566

#	Time	Username	Problem	Language	Result	Execution time	Memory
94566		jasony123123	Palindromic Partitions (CEOI17_palindromic)	C++11	100 / 100	113 ms	27572 KiB

palindromic

#define _CRT_SECURE_NO_WARNINGS
#include <bits/stdc++.h>
//#include <ext/pb_ds/tree_policy.hpp>
//#include <ext/pb_ds/assoc_container.hpp>
using namespace std;
//using namespace __gnu_pbds;

#define FOR(i,start,end) for(int i=start;i<(int)(end);i++)
#define FORE(i,start,end) for(int i=start;i<=(int)end;i++)
#define RFOR(i,start,end) for(int i = start; i>end; i--)
#define RFORE(i,start,end) for(int i = start; i>=end; i--)
#define all(a) a.begin(), a.end()
#define mt make_tuple
#define mp make_pair
#define v vector
#define sf scanf
#define pf printf
#define dvar(x) cout << #x << " := " << x << "\n"
#define darr(x,n) FOR(i,0,n) cout << #x << "[" << i << "]" << " := " << x[i] << "\n"

typedef long long ll;
typedef long double ld;
typedef pair<int, int > pii;
typedef pair<ll, ll> pll;
//template <class T> using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
template<class T> void minn(T &a, T b) { a = min(a, b); }
template<class T> void maxx(T &a, T b) { a = max(a, b); }

void io() {
#ifdef LOCAL_PROJECT 
	freopen("input.in", "r", stdin); freopen("output.out", "w", stdout);
#else 
	/* online submission */

#endif 
	ios_base::sync_with_stdio(false); cin.tie(NULL);
}

const ll MOD = 1000000007LL;
const ll PRIME = 105943LL;
const ll INF = 1e18;
/****************************************************************/
inline ll add(ll a, ll b) { return (a + b) % MOD; }
inline ll mul(ll a, ll b) { return (1LL * a*b) % MOD; }

const int SZ = 1e6 + 1;
ll h[SZ], p[SZ];

void sethash(string &s) {
	FOR(i, 0, s.size())
		h[i + 1] = add(mul(s[i], p[i + 1]), h[i]);
}
ll get(int i, int j) {
	i++, j++;
	return mul(h[j] - h[i - 1] + MOD, p[SZ - i]);
}
void solve() {
	string s; cin >> s;
	sethash(s);
	int n = s.size(), ans = 0;
	int l[2], r[2];
	l[0] = r[0] = 0, l[1] = r[1] = n - 1;
	while (r[0] <= l[1]) {
		while (get(l[0], r[0]) != get(l[1], r[1]))
			r[0]++, l[1]--;
		if (r[0] < l[1]) {
			ans += 2;
			l[0] = r[0] = r[0] + 1;
			l[1] = r[1] = l[1] - 1;
		}
		else {
			ans += 1;
			break;
		}
	}
	cout << ans << "\n";
}
int main() {
	io();
	p[0] = 1;
	FOR(i, 1, SZ) p[i] = mul(p[i - 1], PRIME);
	int t; cin >> t;
	while (t--) solve();
}

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