Submission #519480

#	Time	Username	Problem	Language	Result	Execution time	Memory
519480		Stickfish	Brperm (RMI20_brperm)	C++17	0 / 100	3064 ms	5948 KiB

brperm

#include "brperm.h"
#include <string>
#include <iostream>
#include <vector>
using namespace std;
using ll = long long;

const int MAXN = 500008;
const ll MOD = 1000000007;
const ll MUL = 27;
string s;
ll phash_[MAXN];
ll* phash = phash_ + 1;

ll pw(ll a, ll m) {
    if (!m)
        return 1;
    a %= MOD;
    if (m % 2)
        return (a * pw(a, m - 1)) % MOD;
    return pw(a * a, m / 2);
}

const ll RMUL = pw(MUL, MOD - 2);

ll get_hash(int l, int r) {
    return (MOD + phash[r - 1] - pw(phash[l - 1], MOD - 2)) % MOD * pw(RMUL, l) % MOD;
}

void init(int n, const char s_[]) {
    for (int i = 0; i < n; ++i)
        s.push_back(s_[i]);
    return;
    //ll raymoo = 1;
    //for (int i = 0; i < n; ++i) {
        //phash[i] = (phash[i - 1] + raymoo * (s[i] - 'a')) % MOD;
        //raymoo = (raymoo * MUL) % MOD;
        //cout << phash[i] << ' ';
    //}
    //cout << endl;
    //return;
}

int query(int l, int k) {
    vector<int> ps = {0};
    for (int t = 0; t < k; ++t) {
        for (int i = 0; i < (1 << t); ++i)
            ps.push_back(ps[i] + (1 << (k - t - 1)));
    }
    for (int i = 0; i < (1 << k); ++i) {
        if (s[l + i] != s[l + ps[i]])
            return 0;
    }
    return 1;
    for (auto x : ps)
        cout << x << ' ';
    cout << "$ ";
    ll ans = 0;
    ll pw = 1;
    for (int i = 0; i < (1 << k); ++i) {
        cout << s[ps[i] + l];
        ans = (ans + pw * (s[ps[i] + l] - 'a')) % MOD;
        pw = (pw * MUL) % MOD;
    }
    cout << " | ";
    ll ans0 = 0;
    pw = 1;
    for (int i = 0; i < (1 << k); ++i) {
        cout << s[i + l];
        ans0 = (ans0 + pw * (s[i + l] - 'a')) % MOD;
        pw = (pw * MUL) % MOD;
    }
    cout << ": ";
    cout << ans0 << ' ' << get_hash(l, l + (1 << k)) << ' ';
    return ans == get_hash(l, l + (1 << k));
}

• Subtask 1: 0 / 13
• Subtask 2: 0 / 37
• Subtask 3: 0 / 17
• Subtask 4: 0 / 33