from collections import deque
N=int(input())
ans=[]
dat = [[] for _ in range(N)]
ab=[]
b_d = []
for i in range(N):
    a,b=map(int, input().split())
    ab.append((a,b))
    if a==1:
        dat[i+1].append(i)
    elif b==2:
        b_d.append(i)
    else:
        dq = deque()
        dq.append(i)
        while dq:
            x = dq.pop()
            ans.append(x+1)
            for j in dat[x]:
                dq.append(j)
            if ab[x][1] == 1:
                for j in b_d:
                    dq.append(j)
                b_d = []
for a in ans:
    print(a)