Submission #121597

#	Time	Username	Problem	Language	Result	Execution time	Memory
121597		BigChungus	Palindromic Partitions (CEOI17_palindromic)	C++14	0 / 100	21 ms	8192 KiB

palindromic

#include <bits/stdc++.h>

using namespace std;

#define egal(a, b, c, d) ()

const int N = 1e6 + 7, BASE = 'z' - 'a' + 1;

int MOD[2];

int paw[N][2], hesh[N][2];

string s;

int abs(int val, bool mod) {
    if (val < 0)
        return val + MOD[mod];
    return val;
}

int main()
{
    MOD[0] = 1e9 + 7, MOD[1] = 1e9 + 9;
    ios_base::sync_with_stdio(NULL);
    cin.tie(0);
    cout.tie(0);
    int t;
    cin >> t;
    //hatz putere ca ne trebe impreuna cu hash sa bagam egal(i,j,k,t)
    paw[0][0] = paw[0][1] = 1;
    for (int i = 1; i < N; ++i)
        for (int t = 0; t < 2; ++t)
            paw[i][t] = paw[i - 1][t] * BASE % MOD[t];
    while (t--) {
        cin >> s;
        ///mare hashuri de sa moara dushmanii
        int n = s.size();
        hesh[1][0] = hesh[1][1] = (s[0] - 'a');
        for (int i = 1; i < n; ++i)
            for (int t = 0; t < 2; ++t)
                hesh[i + 1][t] = hesh[i][t] * BASE + (s[i] - 'a');

        int j(1), ans(0);//unde ai ramas, adeverat bossule
        for (int i = 1; i <= n / 2; ++i) {
            if (abs(hesh[i][0] - hesh[j - 1][0] * paw[i - j + 1][0] % MOD[0], 0) == abs(hesh[n - j + 1][0] - hesh[n - i][0] * paw[i - j + 1][0] % MOD[0], 0) && abs(hesh[i][1] - hesh[j - 1][1] * paw[i - j + 1][1] % MOD[1], 1) == abs(hesh[n - j + 1][1] - hesh[n - i][1] * paw[i - j + 1][1] % MOD[1], 1))
                ans += 2, j = i + 1;
        }
        cout << ans + (2 * j - 2 != n) << '\n';
    }

    return 0;
}

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