Given two strings, represented as linked lists (every character is a node in a linked list). Write a function compare() that works similar to strcmp(), i.e., it returns 0 if both strings are the same, 1 if the first linked list is lexicographically greater, and -1 if the second string is lexicographically greater.
Examples:
Input: list1 = g->e->e->k->s->a list2 = g->e->e->k->s->b Output: -1 Input: list1 = g->e->e->k->s->a list2 = g->e->e->k->s Output: 1 Input: list1 = g->e->e->k->s list2 = g->e->e->k->s Output: 0
# Python program to compare two strings # represented as linked lists # A linked list node # structure class Node:
# Constructor to create
# a new node
def __init__( self , key):
self .c = key ;
self . next = None
def compare(list1, list2):
# Traverse both lists. Stop when
# either end of linked list is
# reached or current characters
# don't match
while (list1 and list2 and
list1.c = = list2.c):
list1 = list1. next
list2 = list2. next
# If both lists are not empty,
# compare mismatching characters
if (list1 and list2):
return 1 if list1.c > list2.c else - 1
# If either of the two lists has
# reached end
if (list1 and not list2):
return 1
if (list2 and not list1):
return - 1
return 0
# Driver code list1 = Node( 'g' )
list1. next = Node( 'e' )
list1. next . next = Node( 'e' )
list1. next . next . next = Node( 'k' )
list1. next . next . next . next = Node( 's' )
list1. next . next . next . next . next = Node( 'b' )
list2 = Node( 'g' )
list2. next = Node( 'e' )
list2. next . next = Node( 'e' )
list2. next . next . next = Node( 'k' )
list2. next . next . next . next = Node( 's' )
list2. next . next . next . next . next = Node( 'a' )
print compare(list1, list2)
# This code is contributed by Nikhil Kumar Singh(nickzuck_007) |
Output:
1
Time Complexity: O(M + N), where M and N represents the length of the given two linked lists.
Auxiliary Space: O(1), no extra space is required, so it is a constant.
Please refer complete article on Compare two strings represented as linked lists for more details!