Code for challenges:
##Diagonal Difference https://www.hackerrank.com/challenges/diagonal-difference
##PlusMinus https://www.hackerrank.com/challenges/plus-minus
##Staircase https://www.hackerrank.com/challenges/staircase
To run all the challenges
gulp
To run the Diagonal Difference:
gulp suite-matrix-difference
To run the Plus Minus challenge:
gulp suite-plus-minus
To run the Staircase challenge:
gulp suite-staircase