class Node:

def $\_\_$init$\_\_($self$,$ data$)$:

self.data $=$ data

self.next $=$ None

def length$($head$)$:

count $=0$

while head:

count $+=1$

head $=$ head.next

return count

def check$\_$palindrome$($head$)$:

l $=$ length$($head$)$

t$1=$ head

mid $=$ l $//2$

is$\_$palindrome $=$ True

# Traverse to the midpoint

for i in range$($mid$)$:

t$1=$ t$1.$next

# Reverse the second half of the list

prev $=$ None

while t$1$:

next$\_$node $=$ t$1.$next

t$1.$next $=$ prev

prev $=$ t$1$

t$1=$ next$\_$node

# Compare the first half and the reversed second half

t$1=$ head

t$2=$ prev

for i in range$($mid$)$:

if t$1.$data $!=$ t$2.$data:

is$\_$palindrome $=$ False

break

t$1=$ t$1.$next

t$2=$ t$2.$next

return is$\_$palindrome

def ll$($arr$)$:

if len$($arr$)==0$:

return None

head $=$ Node$($arr$[0])$

last $=$ head

for data in arr$[1$:$]$:

last.next $=$ Node$($data$)$

last $=$ last.next

return head

# Main

# Read the linked list elements including $-1$

arr $=$ list$($int$($i$)$ for i in input$().$strip$().$split$(\text{'}\text{'}))$

# Create a Linked list after removing $-1$ from list

l $=$ ll$($arr$[$:$-1])$

ans $=$ check$\_$palindrome$($l$)$

if ans:

print$("$true$")$

else:

print$("$false$")$