Submission #1338397

#TimeUsernameProblemLanguageResultExecution timeMemory
1338397iamhereforfunPalindromic Partitions (CEOI17_palindromic)C++20
100 / 100
170 ms50828 KiB
// Starcraft 2 enjoyer //

#include <bits/stdc++.h>

// #pragma GCC target("avx2")
// #pragma GCC optimize("O3")
// #pragma GCC optimize("unroll-loops")

using namespace std;

#define LSOne(X) ((X) & -(X))

const int N = 1e6 + 5;
const int K = 1e2 + 5;
const int LG = 20;
const int INF = 1e9 + 5;
const int B = 1000;
// const int MOD1 = 1e9 + 7;
// const int MOD2 = 1e9 + 7;
const int MOD[2] = {(int)1e9 + 7, (int)1e9 + 9};

int n, ans, l, r;
long long pref[2][N], pw10[2][N], inv10[2][N];
string s;

long long pw(long long a, long long b, int i)
{
    long long ans = 1;
    while (b)
    {
        if (b & 1)
            ans *= a;
        a *= a;
        a %= MOD[i];
        ans %= MOD[i];
        b >>= 1;
    }
    return ans;
}

void prep()
{
    for (int x = 0; x < 2; x++)
    {
        pw10[x][0] = 1;
        for (int y = 1; y < N; y++)
        {
            pw10[x][y] = pw10[x][y - 1] * 10;
            pw10[x][y] %= MOD[x];
        }
        inv10[x][N - 1] = pw(pw10[x][N - 1], MOD[x] - 2, x);
        for (int y = N - 2; y >= 0; y--)
        {
            inv10[x][y] = inv10[x][y + 1] * 10;
            inv10[x][y] %= MOD[x];
        }
    }
}

void build()
{
    for (int x = 0; x < 2; x++)
    {
        for (int y = 1; y <= n; y++)
        {
            pref[x][y] = pref[x][y - 1] + (s[y] - 'a' + 1) * pw10[x][y];
            pref[x][y] %= MOD[x];
        }
    }
}

bool chk(int l1, int r1, int l2, int r2)
{
    bool ans = 1;
    for (int x = 0; x < 2; x++)
    {
        long long a = pref[x][r1] - pref[x][l1 - 1];
        a *= inv10[x][l1 - 1];
        a %= MOD[x];
        long long b = pref[x][r2] - pref[x][l2 - 1];
        b *= inv10[x][l2 - 1];
        b %= MOD[x];
        if (a < 0)
            a += MOD[x];
        if (b < 0)
            b += MOD[x];
        ans &= a == b;
    }
    return ans;
}

inline void solve()
{
    cin >> s;
    n = s.length();
    s = '0' + s;
    build();
    ans = 0;
    l = 1, r = n;
    while (l <= r)
    {
        int cl = l, cr = r;
        bool b = 0;
        while (cl < cr)
        {
            // cout << chk(l, cl, cr, r) << " " << l << " " << cl << " " << cr << " " << r << "\n";
            if (chk(l, cl, cr, r))
            {
                ans += 2;
                l = cl + 1;
                r = cr - 1;
                b = 1;
                break;
            }
            else
            {
                cl++;
                cr--;
            }
        }
        // cout << b << " " << l << " " << r << "\n";
        if (!b)
        {
            ans++;
            break;
        }
    }
    cout << ans << "\n";
}

signed main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    prep();
    int t = 1;
    cin >> t;
    for (int x = 1; x <= t; x++)
    {
        solve();
    }
    return 0;
}
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