SDE - Intern

Ayush read about irreducible fractions in the school and made an expression ‘EXPRESSION’ of fraction addition and subtraction.

Note:

An irreducible fraction is a fraction in which the numerator and denominator are integers that have no other common divisors than 1.

Example: 2/3, 8/9, 0/1 are irreducible fractions, where 8/12, 9/12 are not irreducible fractions. 

Expression ‘EXPRESSION’ contains integers from '0' to '9', and characters '/', '+' and '-'.

Each fraction will be an irreducible fraction and will be in the format of ±(numerator/denominator).

Ayush does not know how to solve the expression he made, so he gave you the expression to solve. Your task is to solve the expression.

Note:

Ayush expects your answer to be an irreducible fraction, so if your answer is an integer, convert it into an irreducible fraction by putting 1 in the denominator.

For example, if your answer is "9", then print "9/1" (without quotes). 

You are given a list of ‘N’ words ‘WORDS’. Your task is to return all pairs of the distinct indices (i, j) in ‘WORDS’, such that the concatenation of WORDS[i] and WORDS[j] is a palindrome.

For Example:

You are given ‘WORDS’ = [“cat”, “mat”, “tac”]. Then the answer will be [(0, 2), (2, 0)}, because “cat” + “tac” = “cattac” which is a palindrome and “tac” + “cat” = “taccat” which is also a palindrome.

You are given two Singly Linked Lists of integers, which may have an intersection point.

Your task is to return the first intersection node. If there is no intersection, return NULL.

Example:-

The Linked Lists, where a1, a2, c1, c2, c3 is the first linked list and b1, b2, b3, c1, c2, c3 is the second linked list, merging at node c1.