Submission #419429

#	Time	Username	Problem	Language	Result	Execution time	Memory
419429		Bill_00	Crayfish scrivener (IOI12_scrivener)	C++14	100 / 100	615 ms	109892 KiB

scrivener

#include <bits/stdc++.h>
using namespace std;
char last;
int a[1000005][25],cnt,lol[1000005],sz[1000005];
char x[1000005];
void Init() {}
int find(int num){
	return lol[num]=(lol[num]==num?num:find(lol[num]));
}
void TypeLetter(char L) {
	cnt++;
	x[cnt]=L;
	sz[cnt]=sz[find(cnt-1)]+1;
	lol[cnt]=cnt;
	a[cnt][0]=find(cnt-1);
	for(int i=1;i<=20;i++){
		a[cnt][i]=a[a[cnt][i-1]][i-1];
	}
}

void UndoCommands(int U) {
	cnt++;
	lol[cnt]=find(cnt-U-1);
	sz[cnt]=sz[find(cnt-U-1)];
}
char GetLetter(int P) {
	int siz=sz[find(cnt)];
	int k=siz-P-1;
	int y=find(cnt);
	for(int i=20;i>=0;i--){
		if(k>=(1<<i)){
			y=a[y][i];
			k-=(1<<i);
		}
	}
	return x[y];
}

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