n,head,key=map(int,input().split())
a=[]
for i in range(n):
    x,y=map(int,input().split())
    a.append([x,y])
a.append([key,-1])
p=head;pre=-1
while p!=-1 and key!=a[p][0]:
    pre=p
    p=a[p][1]
if pre==-1:
    head=a[head][1]
else:
    a[pre][1]=a[p][1]
p=head
while p!=-1:
    print(a[p][0],end=" ")
    p=a[p][1]