Submission #72959

#	Time	Username	Problem	Language	Result	Execution time	Memory
72959		Hoget157	Crayfish scrivener (IOI12_scrivener)	C++14	34 / 100	1020 ms	127232 KiB

scrivener

struct Node{
	public:
	int num;
	char c;
	Node* par[22] = {};
};

int cnt;
Node *root,*p[1000010];

void Init() {
	cnt = 0;
	root = new Node;
	root->num = -1;
	p[cnt++] = root;
}

void TypeLetter(char L) {
	Node *tmp = p[cnt - 1];
	p[cnt] = new Node;
	p[cnt]->c = L;
	p[cnt]->par[0] = tmp;
	p[cnt]->num = tmp->num + 1;
	for(int i = 1;i < 22;i++){
		if(p[cnt]->par[i - 1]) p[cnt]->par[i] = p[cnt]->par[i - 1]->par[i - 1];
		else break;
	}
	cnt++;
}

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

char GetLetter(int P) {
	Node *tmp = p[cnt - 1];
	for(int i = 0;i < 22;i++){
		if(tmp->num == P) break;
		if(((tmp->num - P) >> i) & 1) tmp = tmp->par[i];
	}
	return tmp->c;
}

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