#include <stdio.h>
#include <stdlib.h>

typedef char ELEMTYPE;

typedef struct LinkedList {
	struct LinkedList* prev;
	struct LinkedList* next;
	ELEMTYPE elem;
} Node;

typedef struct MyList {
	Node* header;
	Node* trailer;
	int size;
} MyList;

Node* getNode()
{
	Node* node = (Node*)malloc(sizeof(Node));
	node->prev = NULL;
	node->next = NULL;
	node->elem = 0;

	return node;
}

ELEMTYPE putNode(Node* node)
{
	ELEMTYPE e = node->elem;
	free(node);

	return e;
}

void init(MyList* l)
{
	l->header = getNode();
	l->trailer = getNode();

	l->header->next = l->trailer;
	l->trailer->prev = l->header;

	l->size = 0;
}

void get(MyList* l, int r)
{
	Node* node = l->header;

	if (!(1 <= r && r <= l->size)) {
		printf("invalid position\n");
		return;
	}

	while (r--)
		node = node->next;
	printf("%c\n", node->elem);
}

void print(MyList* l)
{
	Node* node = l->header->next;

	while (node != l->trailer) {
		printf("%c", node->elem);
		node = node->next;
	}
	printf("\n");
}

void add(MyList* l, int r, ELEMTYPE e)
{
	Node* p = l->header, * newNode;

	if (!(1 <= r && r <= l->size + 1)) {
		printf("invalid position\n");
		return;
	}

	newNode = getNode();
	newNode->elem = e;

	while (--r)
		p = p->next;

	newNode->next = p->next;
	newNode->prev = p;
	p->next->prev = newNode;
	p->next = newNode;

	l->size++;
}

void delete(MyList* l, int r)
{
	Node* delNode = l->header;

	if (!(1 <= r && r <= l->size)) {
		printf("invalid position\n");
		return;
	}

	while (r--)
		delNode = delNode->next;

	delNode->prev->next = delNode->next;
	delNode->next->prev = delNode->prev;
	l->size--;

	putNode(delNode);
}

void deleteAll(MyList* l)
{
	while (l->size)
		delete(l, 1);

	putNode(l->header);
	putNode(l->trailer);
	free(l);
}

int main(void)
{
	MyList* l = (MyList*)malloc(sizeof(MyList));
	int N;
	scanf("%d%*c", &N);

	init(l);
	while (N--)
	{
		char command, elem;
		int rank;
		scanf("%c", &command);

		switch (command)
		{
		case 'A':
			scanf("%d %c", &rank, &elem);
			add(l, rank, elem);
			break;
		case 'D':
			scanf("%d", &rank);
			delete(l, rank);
			break;
		case 'G':
			scanf("%d", &rank);
			get(l, rank);
			break;
		case 'P':
			print(l);
			break;
		default:
			break;
		}
		getchar();
	}
	deleteAll(l);
	return 0;
}