Mr.savani is collecting a money from n students for a trip, like collect $1 from 1st student, $3 from 3rd student and so on.. but it should not include k (unlucky number) into sum. if it includes k into sum, then ignore that student

Example:

n = number of student, k = unlucky number i/p: 2,2, o/p: 3, i/p: 3,3, o/p: 5, (could be 4 as well but find max sum)

Solution: Using

Discriminantmaths D = b^{2}– 4ac

def maxMoney(n, k) sum = (n * (n + 1)) / 2 sum -= 1 if Math.sqrt(1+8*k) % 1 == 0 return sum end puts maxMoney(2,2) # o/p 3 puts maxMoney(2,1) # o/p 2 puts maxMoney(3,3) # o/p 5 puts maxMoney(2000000000,4000000000000000)