Submission #68469

#	Time	Username	Problem	Language	Result	Execution time	Memory
68469		nvmdava	Crayfish scrivener (IOI12_scrivener)	C++17	34 / 100	1070 ms	21744 KiB

scrivener

#include <bits/stdc++.h>
using namespace std;
char s[1000001];
int now = 0, i = 1, dir[1000001][21], sz[1000001];
void Init() {}

int find(int i, int x){
	if(sz[i] == x){
		return i;
	}
	int j = 0;
	while(sz[i] - (1 << j) >= x)j++;
	j--;
	return find(dir[i][j], x);
}

void TypeLetter(char L) {
	s[i] = L;
	dir[i][0] = now;
	sz[i] = sz[now] + 1;
	for(int j = 0; j < 21; j++){
		if(sz[i] <= (1 << j)) break;
		dir[i][j] = find(now, sz[i] - (1 << j));
	}
	now = i;
	i++;
}
 
void UndoCommands(int U) {
	now = i - U - 1;
	s[i] = s[now];
	for(int j = 0; j <= 20; j++)dir[i][j] = dir[now][j];
	sz[i] = sz[now];
	i++;
}

char GetLetter(int P) {
	return s[find(i - 1, P + 1)];
}

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