Learn to Program with C_ Learn to Program using the Popular C Programming Language ( PDFDrive )

Chapter 9 ■ Searching, Sorting, and Merging
Write a program to read a set of n arbitrary positive integers (assume n < 100) and
print their mode; n is not given but 0 indicates the end of the data.
Write an efficient program to find the mode if it is known that the numbers all
lie between 1 and 999, inclusive, with no restriction on the amount of numbers
supplied; 0 ends the data.
8. An array num contains k numbers in num[0] to num[k-1], sorted in descending
order. Write a function insertInPlace which, given num, k and another number
x, inserts x in its proper position such that num[0] to num[k] are sorted in
descending order. Assume the array has room for x.
9. A multiple-choice examination consists of 20 questions. Each question has 5
choices, labeled A, B, C, D, and E. The first line of data contains the correct answers
to the 20 questions in the first 20 consecutive character positions, for example:
BECDCBAADEBACBAEDDBE
Each subsequent line contains the answers for a candidate. Data on a line consists
of a candidate number (an integer), followed by 1 or more spaces, followed by the
20 answers given by the candidate in the next 20 consecutive character positions.
An X is used if a candidate did not answer a particular question. You may assume
all data are valid and stored in a file exam.dat. A sample line is:
4325 BECDCBAXDEBACCAEDXBE
There are at most 100 candidates. A line containing a “candidate number” 0 only
indicates the end of the data.
Points for a question are awarded as follows:– correct answer: 4 points; wrong
answer: -1 point; no answer: 0 points.
Write a program to process the data and print a report consisting of candidate
number and the total points obtained by the candidate, in ascending order by
candidate number. At the end, print the average number of points gained by the
candidates.
10. An array A contains integers that first increase in value and then decrease in value,
for example:
It is unknown at which point the numbers start to decrease. Write efficient code to
copy the numbers from A to another array B so that B is sorted in ascending order.
Your code must take advantage of the way the numbers are arranged in A. (Hint:
perform a merge starting at both ends.)
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