Find the equilibrium point
Find a point in an array where sum of left side array members(wrt to that point) and right side(wrt to that point) are equal..in other words equilibrium point.
Given an integer n, write a function that returns count of trailing zeroes in n!. Examples: Input: n = 5 Output: 1 Factorial of 5 is 20 which has one trailing 0. Input: n = 20 Output: 4 Factorial of 20 is 2432902008176640000 which has 4 trailing zeroes. Input: n = 100 Output: 24
SL[i] = sum of numbers from 0 to i (i.e. running sum from left)
ReplyDeleteSR[i] = sum of numbers from n-1 to n-i-1 (i.e. running sum from right)
You can build the above two SR,SL in O(n) by doing simple scans from left and right respectively.
Now again do another O(n) check to see if there is an x such that SL[x] = SR[n-x-1].
@Wrick so for every i ,you will find out SL[i] and SR[i] which is o(n) so overall it will take o(n^2).we need less than that.
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