You are suggested to use recursive techniques to solve this problem. the ith queen's placement at the current grid position is dependent on whether all the following i+1(th) to (n-1)th queens can find their positions. note that in c, an array starts with index 0, so the (n-1)th queen is the last one. here is some pseudocode to get you started, which you should stick as closely as possible to when implementing your solution. the definition of n controls the size of the grid:

Larry sent an email to andy. andy didn't open larry's email but still understood what the message was. how did andy determine the message without opening the email?

Some of your friends have gotten into the burgeoning field of time-series data mining, in which one looks for patterns in sequences of events that occur over time. purchases at stock exchanges--what’s being bought-- are one source of data with a natural ordering in time. given a long sequence s of such events, your friends want an efficient way to detect certain "patterns" in them--for example, they may want to know if the four events buy yahoo, buy ebay, buy yahoo, buy oracle occur in this sequence s, in order but not necessarily consecutively. they begin with a collection of possible events (e.g., the possible’ transactions) and a sequence s of n of these events. a given event may occur multiple times in s (e.g., yahoo stock may be bought many times in a single sequence s). we will say that a sequence s’ is a subsequence of s if there is a way to delete certain of the events from s so that the remaining events, in order, are equal to the sequence s’. so, for example, the sequence of four events above is a subsequence of the sequence buy amazon, buy yahoo, buy ebay, buy yahoo, buy yahoo, buy oracle their goal is to be able to dream up short sequences and quickly detect whether they are subsequences of s. so this is the problem they pose to you: give an algorithm that takes two sequences of even~s--s’ of length m and s of length n, each possibly containing an event more than once--and decides in time o(m n) whether s’ is a subsequence of s

What is the total resistance in a circuit that contains three 60 ohm resistors connected in a series? a. 20 ohms b. 120 ohms c. 60 ohms d. 180 ohms