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 other words equilibrium point.


  1. SL[i] = sum of numbers from 0 to i (i.e. running sum from left)
    SR[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].

  2. @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.


Post a Comment

Popular posts from this blog