CS202 Computer Science II

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Assignment 4
Due Oct 19th before 9:00 a.m. in class

Last modified 10/11/98 @ 5:00 p.m.
A Makefile, and Turnin intructions

This assignment will get you more familiar with recursion.

Write a recursive version of the binary search algorithm that takes an integer key value and a sorted array of integers as its input and searches for the key in the array.

Your program should read a sorted list of integers from standard input, search for the key (specified on the command line), and output the index of the key in the list, if found, and an appropriate message if the key is not found. Both the number of integers to be read and the key are specified on the command line.

	% bsearch 10 25

would read 10 integers from standard input into an array and search for the value 25. In general, bsearch will be invoked as follows:

	% bsearch n key

where

n is the number of integers to read
key is the integer that we are looking for.

Your output should also indicate the number of comparisons made. Here are some examples with my inputfile file named Intinput.

% bsearch 23 162 < Intinput
Found 162 in location  9 after 4 Comparisons  
% bsearch 23 629 < Intinput
Found 629 in location  22 after 4 Comparisons   
% bsearch 24 629 < Intinput  
Found 629 in location  22 after 5 Comparisons  
% bsearch 24 19 < Intinput 
Could not find 19 in array after 4 Comparisons

Here is my main source file (as4.cpp) provided as a template.

Constraints

ReadInput() is expected to be in a file named io.cpp and
BSearch() to be in the file bsearch.cpp

Good Luck. Start on the assignment now.

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