Also if u have n numbers u can also find the greatest by performing below method

result = (sum + |diff|)/2

max = (result + |diff between next number and result|)/2

Repeat it until no number is left

For example
let assume I have 3 numbers in variable a, b, c

r = (a + b + |a - b|)/2
max = (r + c + |r - c|)/2

#tips