How to find max. and min. in array using minimum comparisons?

Question

This is a interview question: given an array of integers find the max. and min. using minimum comparisons.

Obviously, I can loop over the array twice and use ~

Answer 1

go for divide and conquer !

1,3,2,5

for this finding min,max will take 6 comparisons

but divide them

1,3 ---> will give min 1 and max 3 in one comparison
2,5 ---> will give min 2 and max 5 in one comparison 

now we can compare two mins and maxs

min(1,2) --> will give the final min as 1 (one comparison)
max(3,5) ---> will give the final max as 5 (one comparison)

so totally four comparisons to find both min and max.