Submission #494419

#	Time	Username	Problem	Language	Result	Execution time	Memory
494419		jasen_penchev	Brperm (RMI20_brperm)	C++14	100 / 100	1996 ms	168664 KiB

brperm

#include "brperm.h"
#include <iostream>
#define endl '\n'
using namespace std;

const int MAXN = 500000;
const int LOG = 20;
const int BASE = 26;
const int MOD = 1000000007;

int n;
int pw[MAXN + 1];

struct Hash
{
    int len;
    int num;
};

Hash operator + (Hash h1, Hash h2)
{
    Hash ret;
    ret.len = h1.len + h2.len;
    ret.num = (1ll * h1.num * pw[h2.len] + h2.num) % MOD;
    return ret;
}

bool operator == (Hash h1, Hash h2)
{
    return (h1.len == h2.len and h1.num == h2.num);
}

Hash h1[MAXN + 1][LOG + 1];
Hash h2[MAXN + 1][LOG + 1];

void init(int n0, const char s[])
{
    n = n0;

    pw[0] = 1;
    for (int i = 1; i <= MAXN; ++ i)
    {
        pw[i] = (1ll * pw[i - 1] * BASE) % MOD;
    }

    for (int i = 0; i < n; ++ i)
    {
        h1[i][0].len = 1;
        h1[i][0].num = s[i] - 'a';
    }

    for (int j = 1; j <= LOG; ++ j)
    {
        for (int i = 0; i < n - (1ll << (j - 1)); ++ i)
        {
            h1[i][j] = h1[i][j - 1] + h1[i + (1ll << (j - 1))][j - 1];
        }
    }

    for (int j = 0; j <= LOG; ++ j)
    {
        for (int i = 0; i < n; ++ i)
        {
            h2[i][j].len = 1;
            h2[i][j].num = s[i] - 'a';
        }
        for (int k = j - 1; k >= 0; -- k)
        {
            for (int i = 0; i < n - (1ll << k); ++ i)
            {
                h2[i][j] = h2[i][j] + h2[i + (1ll << k)][j];
            }
        }
    }

    return;
}

int query(int pos, int k)
{
    if (pos + (1ll << k) > n) return 0;
    return (h1[pos][k] == h2[pos][k]);
}

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