Submission #63018

#	Time	Username	Problem	Language	Result	Execution time	Memory
63018		theknife2001	Crayfish scrivener (IOI12_scrivener)	C++17	60 / 100	1032 ms	141888 KiB

scrivener

#include <bits/stdc++.h>


using namespace std;
const int N=1e6+55;
int trie[N*2][26];
char letter[N];
int p[N][22];
int a[N];
int l[N];
int node;
int cnt=1;
int k=1;

void Init()
{
    node=cnt++;
}

int c,temp,nd;
void TypeLetter(char L)
{
    c=L-'a';
    temp=node;
    if(!trie[node][c])
        trie[node][c]=cnt++;
    node=trie[node][c];
    letter[node]=L;
    a[k]=node;
    l[k]=l[k-1]+1;
    if(p[node][0]==0)
    {
        p[node][0]=temp;
        for(int i=1;i<20;i++)
            p[node][i]=p[p[node][i-1]][i-1];
    }
    k++;
}

void UndoCommands(int U)
{
    node=a[k-U-1];
    l[k]=l[k-U-1];
    a[k]=node;
    k++;
}
char GetLetter(int P)
{
    P=l[k-1]-P-1;
    nd=node;
    for(int i=19;i>=0;i--)
    {
        if(P&(1<<i))
            nd=p[nd][i];
    }
    return letter[nd];
}

• Subtask 1: 5 / 5
• Subtask 2: 7 / 7
• Subtask 3: 22 / 22
• Subtask 4: 26 / 26
• Subtask 5: 0 / 40