Activity selectivity problem

#1

my first test case is not passing second is passing

#2

You need to sort ending times in ascending order and then pick the activities greedily.

#3

can you how to use sort function in pairs i am not able to wrie syntax for ending time

#4
#5

oh my compare function was already correct what i haven’t done was that last variable k update to be in if block i maked it out of if block but now done thx btw