Question $3$: There are $n$ activities with their start and finish times. We write the following

pseudocode so that a machine can perform a maximum number of activities. Assume that the

machine can do only a single activity at a time. Here is an sample input$/$output:

Input: start$[]=\{10,12,20\},$ finish $[]=\{20,25,30\}$

Output: $02$

Explanation: A person can perform at most two activities. The

maximum set of activities that can be executed

is $\{0,2\}[$ These are indexes in start$[]$ and finish$[]]$

Input: start$[]=\{1,3,0,5,8,5\},$ finish $[]=\{2,4,6,7,9,9\}$;

Output: $0134$

Explanation: A person can perform at most four activities. The

maximum set of activities that can be executed

is $\{0,1,3,4\}[$ These are indexes in start $[]$ and finish$[]$

Sort activities according to their finishing time

Select the first activity from the sorted array and print $t_{{?}_{?}}$

For each remaining activity in the sorted array

If the start time of the current activity is greater than or equal to the finish time

of the previously selected activity

Select this activity and print it

endlf

endFor

Is it a greedy algorithm? If yes, justify your answer. If no$,$ what kind of problem$-$solving

approach best describes this pseudocode? Also, what is the time complexity of this

pseudocode?