How do I search for a number in a 2d array sorted left to right and top to bottom?

Question

I was recently given this interview question and I\'m curious what a good solution to it would be.

Say I\'m given a 2d array where all the numbers i

Answer 1

Binary search through the diagonal of the array is the best option. We can find out whether the element is less than or equal to the elements in the diagonal.