"""

https://yukicoder.me/problems/no/3086

"""

import sys
from sys import stdin

N = int(stdin.readline())

A = []
B = []

for i in range(N):
    a,b = map(int,stdin.readline().split())
    A.append(a)
    B.append(b)


re = {}

two = []

ans = []

def put(i):
    ans.append(i+1)
    if i in re:
        put(re[i])

for i in range(N):

    if A[i] == 1:
        re[i+1] = i

    if B[i] == 2:
        two.append(i)

    if B[i] == 1:
        re[i] = two[-1]


rev = set( re.values() )

for i in range(N):
    if i not in rev:
        put(i)

print (*ans,sep="\n")