This problem was asked by Facebook.
Given an array of integers, write a function to determine whether the array could become non-decreasing by modifying at most 1 element.
For example, given the array [10, 5, 7], you should return true, since we can modify the 10 into a 1 to make the array non-decreasing.
Given the array [10, 5, 1], you should return false, since we can't modify any one element to get a non-decreasing array.