Write a program to grade an n-question multiple-choice exam (for n between 5 and 50) and provide feedback about the most frequently missed questions. Your program will take data from the file examdat. txt. The first line of the file contains the number of questions on the exam followed by a space and then an n-character string of the correct answers. Write a function fgets Answers that inputs the answers from an open input file. Each of the lines that follow contain an integer student ID followed by a space and then that stu dent's answers. Function fgets Answers can also be called to input a student's answers. Your program is to produce an output file, report. txt, containing the answer key, each student's ID, and each student's score as a percentage, and then information about how many students missed each question. Here is a short sample input and output files. examdat. txt 5 dbbac 111 dabac 102 dcbde 251 dbbac

The idea that, for each pair of devices v and w, there’s a strict dichotomy between being “in range” or “out of range” is a simplified abstraction. more accurately, there’s a power decay function f (·) that specifies, for a pair of devices at distance δ, the signal strength f(δ) that they’ll be able to achieve on their wireless connection. (we’ll assume that f (δ) decreases with increasing δ.) we might want to build this into our notion of back-up sets as follows: among the k devices in the back-up set of v, there should be at least one that can be reached with very high signal strength, at least one other that can be reached with moderately high signal strength, and so forth. more concretely, we have values p1 ≥ p2 ≥ . . ≥ pk, so that if the back-up set for v consists of devices at distances d1≤d2≤≤dk,thenweshouldhavef(dj)≥pj foreachj. give an algorithm that determines whether it is possible to choose a back-up set for each device subject to this more detailed condition, still requiring that no device should appear in the back-up set of more than b other devices. again, the algorithm should output the back-up sets themselves, provided they can be found.\