##### ###### ##### ### # # ### # # ###### ## ## ## ## ## ## ## # # # # # ## ##### #### ##### # # # # # # # #### ## # ## ## ## ## # # # # # ## ## # ###### ## ### # ### # ######
##### ###### ##### ### # # ### # # ###### ## ## ## ## ## ## ## # # # # # ## ##### #### ##### # # # # # # # #### ## # ## ## ## ## # # # # # ## ## # ###### ## ### # ### # ######
Narrowing the range
The squares form an increasing sequence. This means you can use binary search.
Start with and . Compute and check . If , you found it. If , search the right half. If , search the left half.
Watch out for overflow when computing . If is large, the product might exceed integer limits.
