Pairwise Consecutive Elements
Submissions: 3711   Accuracy:


  Difficulty: Basic   Marks: 1

Given a stack of integers of size N, your task is to complete the function pairWiseConsecutive(), that checks whether numbers in the stack are pairwise consecutive or not. The pairs can be increasing or decreasing, and if the stack has an odd number of elements, the element at the top is left out of a pair. The function should retain the original stack content.

Only following standard operations are allowed on stack.

  • push(X): Enter a element X on top of stack.
  • pop(): Removes top element of the stack.
  • empty(): To check if stack is empty.


Input : stack = [4, 5, -2, -3, 11, 10, 5, 6, 20]
Output : Yes
Each of the pairs (4, 5), (-2, -3), (11, 10) and
(5, 6) consists of consecutive numbers.

Input : stack = [4, 6, 6, 7, 4, 3]
Output : No
(4, 6) are not consecutive.

The function takes a single argument as input, a stack object 's' of type int that contain the elements.
There will be T test cases and for each test
case the function will be called separately.

For each
testcase output a single line containing "Yes"(without quote) if the elements of the stack is pairwise consecutive, else print "No".



1 2 3 4 5 6
1 5 3 9 7


Note:The Input/Ouput format and Example given are used for system's internal purpose, and should be used by a user for Expected Output only. As it is a function problem, hence a user should not read any input from stdin/console. The task is to complete the function specified, and not to write the full code.

** For More Input/Output Examples Use 'Expected Output' option **

Contributor: Harshit Sidhwa
Author: support3

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