Submission #835290

#	Time	Username	Problem	Language	Result	Execution time	Memory
835290		Kerim	Crayfish scrivener (IOI12_scrivener)	C++17	100 / 100	329 ms	70064 KiB

scrivener

#define MAXN 2000003
#include "bits/stdc++.h"
using namespace std;

const int LOGN=21;
int nd, now, P[MAXN][LOGN], lvl[MAXN];
vector<int> where;
char arr[MAXN];

void Init() {}

char get(int x){
  	int tmp = now;
	for(int i = LOGN-1; i>=0; i--)
		if (x >= (1<<i))
			tmp = P[tmp][i], x -= (1<<i);
	return arr[tmp];
}	

void TypeLetter(char L) {
  	int to = ++nd;
    arr[to] = L;
	P[to][0] = now;
  	lvl[to] = lvl[now]+1;
  	now = nd;
	for(int i=1;i<LOGN;i++)
		if(P[now][i-1])
			P[now][i]=P[P[now][i-1]][i-1];
 	where.push_back(now);
}

void UndoCommands(int U) {
	now = where[int(where.size())-U-1];
  	where.push_back(now);
}

char GetLetter(int P) {
	return get(lvl[now]-P-1);
}

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