N=int(input())
from collections import deque
d=deque()
A=[deque() for i in range(N)] 
for i in range(N):
  A[i].append(i+1)
  
d=deque()
ans=[]
for i in range(N):
  a,b=map(int,input().split())
  if a+b==0:
    while A[i]:
      c=A[i].popleft()
      ans.append(c)
  elif b==2:
    while A[i]:
      c=A[i].popleft()
      d.append(c)
  if b==1:
    while d:
      c=d.popleft()
      A[i].append(c)
  if a==1:
    while A[i]:
      c=A[i].popleft()
      A[i+1].append(c)
      
for i in range(N):
  while A[i]:
    c=A[i].popleft()
    ans.append(c)
    
for c in ans:
  print(c)