from collections import deque

M = int(input())


# 默认下标是0的位置是虚拟头结点，所以多分一个位置
node = [0] * (M+1)
next = [0] * (M+1)
next[0] = -1
avai_pos = deque()   # 可用的位置
for i in range(1, M+1):
    avai_pos.append(i)

time_stamp2pos = {0:0}     # 时间戳到存放索引的映射


time_stamp = 1
for _ in range(M):
    s = input()
    if s[0] == 'H':
        val = int(s.split()[1])
        new_pos = avai_pos.popleft()
        next[new_pos] = next[0]
        next[0] = new_pos
        node[new_pos] = val
        time_stamp2pos[time_stamp] = new_pos
        time_stamp += 1

    elif s[0] == 'I':
        k, val = map(int, s.split()[1:])
        cur_pos = time_stamp2pos[k]
        new_pos = avai_pos.popleft()
        next[new_pos] = next[cur_pos]
        next[cur_pos] = new_pos
        node[new_pos] = val
        time_stamp2pos[time_stamp] = new_pos
        time_stamp += 1

    else:
        k = int(s.split()[1])
        cur_pos = time_stamp2pos[k]
        if next[cur_pos] != -1:
            next_pos = next[cur_pos]
            next[cur_pos] = next[next_pos]
            next[next_pos] = -1
            avai_pos.append(next_pos)

cur_pos = next[0]
ans = []
while cur_pos !=- 1:
    ans.append(node[cur_pos])
    cur_pos = next[cur_pos]

print(' '.join(map(str, ans)))