Submission #98735

#	Time	Username	Problem	Language	Result	Execution time	Memory
98735		Alexa2001	Crayfish scrivener (IOI12_scrivener)	C++17	34 / 100	1060 ms	165112 KiB

scrivener

#include <bits/stdc++.h>

using namespace std;

const int Nmax = 1e6 + 5, lg = 20;

int nodes, t[lg+2][Nmax], p[lg+2][Nmax], up[Nmax];
char letter[Nmax];

void Init()
{
}

void TypeLetter(char L)
{
    letter[++nodes] = L;
    t[0][nodes] = nodes - 1;
    p[0][nodes] = nodes - 1;
    up[nodes] = up[nodes - 1] + 1;

    int i;
    for(i=1; i<=lg; ++i)
        t[i][nodes] = t[i-1][t[i-1][nodes]],
        p[i][nodes] = p[i-1][p[i-1][nodes]];
}

void UndoCommands(int U)
{
    p[0][nodes + 1] = nodes;

    int cursor = nodes, i;
    for(i=0; i<=lg; ++i)
        if(U & (1<<i)) cursor = p[i][cursor];

    t[0][nodes + 1] = cursor;
    up[++nodes] = up[cursor];

    for(i=1; i<=lg; ++i)
        t[i][nodes] = t[i-1][t[i-1][nodes]],
        p[i][nodes] = p[i-1][p[i-1][nodes]];
}

char GetLetter(int P)
{
    int i, x = nodes; ++P;
    for(i=lg; i>=0; --i)
        if(up[t[i][x]] >= P) x = t[i][x];
    return letter[x];
}

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