Submission #3189

#	Time	Username	Problem	Language	Result	Execution time	Memory
3189		cki86201	Crayfish scrivener (IOI12_scrivener)	C++98	100 / 100	700 ms	87992 KiB

scrivener

const int MX = 1000010;
char p[MX];
int up[MX][20],a[MX],cnt,dep[MX];

void Init(){dep[0]=-1;}

void TypeLetter(char L){
	++cnt;
	p[cnt]=L;
	a[cnt]=cnt;
	up[cnt][0]=a[cnt-1];
	dep[cnt]=dep[a[cnt-1]]+1;
	int i,tmp=up[cnt][0];
	for(i=1;i<20;i++){
		if(up[tmp][i-1]){
			up[cnt][i]=up[tmp][i-1];
			tmp=up[cnt][i];
		}
		else break;
	}
}

void UndoCommands(int U){
	a[cnt+1]=a[cnt-U];
	cnt++;
}

char GetLetter(int P){
	int i,tmp=a[cnt];
	for(i=19;i>=0;i--){
		if(dep[up[tmp][i]]<P)continue;
		tmp=up[tmp][i];
	}
	return p[tmp];
}

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