Astack of fake coins there are n stacks of n identical-looking coins. all ofthe coins in one of these stacks are counterfeit, while all the coins in the otherstacks are genuine. every genuine coin weighs 10 grams; every fake weighs11 grams. you have an analytical scale that can determine the exact weight ofany number of coins. a. devise a brute-force algorithm to identify the stack with the fake coins anddetermine its worst-case efficiency class. b. what is the minimum number of weighings needed to identify the stackwith the fake coins?