Introduction to C Problem Set 3 CS 2022 Spring 2011 Due Friday 25 February 2011 1 Puzzle Bitwise Operation 20 pts In this problem you will implement the following functions according to their requirements Each function has a list of legal operations and a maximum number operations that you can use int bit and int x int y Returns x y Example bit and 6 5 4 Max ops 8 Legal ops int bit or int x int y Returns x y Example bit or 6 5 7 Max ops 8 Legal ops int is equal int x int y Returns 1 if x y and 0 otherwise Example is equal 5 5 1 is equal 4 5 0 Max ops 5 Legal ops int logical right shift int x int n Does a logical right shift of x to the right by n Example logical right shift 0x87654321 4 0x08765432 Max ops 16 Legal ops Download code template bit op zip from CMS 1 The only file you need to edit is bit op c I provide a Makefile for you to compile the code There are also test cases in bit op c you should not edit them When you are done compress the files again and submit the zip file bit op zip to CMS 1 https cms csuglab cornell edu 1 2 I O File I O 40 pts There is a very useful Unix tool called cat It is used to concatenate files If there are command line arguments they are interpreted as filenames and processed in order If there are no arguments the standard input is processed You need to print error message when files are not found In this problem you will implement this tool Write your code in cat c and submit it to CMS If you compile your code to cat you will expect it has the same behavior as the Unix tool cat 3 Multithreading Threads 40 pts Recall that in assignment 1 we have evaluated the performance of a C program which outputs any vector pair whose cosine similarity is greater than or equal to a user defined threshold In this problem you will write a multi threaded version Download calc c and vectors bin from CMS first vectors bin is a binary file storing a 2 dimensional double array row by row There are 10000 vectors in this file and each vector has 100 dimensions Your program should read the data from vectors bin first and create at least two threads to speed up the all pairs computation You should also write a Makefile to manage your project The program will output the number of vector pairs that pass the threshold and the running time directly Finally compress your calc c and Makefile to code zip and submit it to CMS 4 Bonus More on Bitwise Operations 20 pts Implement the following functions int least bit pos int x Returns a mask that marks the position of the least significant 1 bit of x Example least bit pos 96 0x20 Max ops 30 Legal ops int sat add int x int y Adds two values and if the result x y has a positive overflow it returns the greatest possible positive value instead of getting a negative result If the result has a negative overflow then it should return the least possible negative value Example sat add 0x40000000 0x40000000 0x7fffffff sat add 0x80000000 0xffffffff 0x80000000 Max ops 30 Legal ops 2 Download bonus zip from CMS in which bonus c is the file you need to edit There are test cases in the main function You only need to implement the functions Finally submit your bonus zip to CMS 3