Given an array whose elements are either 1 or 0, find i and j such that 0<=i<=j<arr.size and we get maximum number of 1 after we flip 0 to 1 and 1 to 0 within range [i,j]
Flip bits to get max number of 1 in array

find the maximum number zeros in an array with one flip of a subarray allowed. A flip operation switches all 0s to 1s and 1s to 0s.
http://www.geeksforgeeks.org/maximizenumber0sflippingsubarray/