Submission #500288

#	Time	Username	Problem	Language	Result	Execution time	Memory
500288		pooyashams	Palindromic Partitions (CEOI17_palindromic)	C++14	100 / 100	51 ms	15044 KiB

palindromic

#include <algorithm>
#include <iostream>
#include <numeric>
#include <cstring>
#include <iomanip>
#include <vector>
#include <bitset>
#include <stack>
#include <queue>
#include <cmath>
#include <set>
#include <map>

using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<int, int> pii;

const int maxn = 1e6+10;
const int base = 541;
const int mod = 1e9+7;

int kmp[maxn];
int bpw[maxn];
int n;
string str;

inline void solve()
{
	cin >> str;
	n = str.size();
	int o = 0;
	int s = 0;
	int e = n-1;
	int h1 = str[s++];
	int h2 = str[e--];
	int l = 1;
	int mid = n/2 - (1-n%2);
	for(int i = 0; i < mid; i++)
	{
		if(h1 == h2)
		{
			o += 2;
			h1 = str[s++];
			h2 = str[e--];
			l = 1;
		}
		else
		{
			h1 = (1ll*h1*base+str[s++]) % mod;
			h2 = (1ll*bpw[l++]*str[e--]+h2) % mod;
		}
	}
	if(h1 == h2 and n % 2 == 0)
		o += 2;
	else
		o += 1;
	cout << o << endl;
}

int32_t main()
{
	ios::sync_with_stdio(false);
	cin.tie(0);
	bpw[0] = 1;
	for(int i = 1; i < maxn; i++)
		bpw[i] = 1ll*bpw[i-1]*base%mod;
	int T; cin >> T;
	while(T--)
	{
		solve();
	}
	return 0;
}

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