#Assignment – 1 You are to write a simple C program that will take a decimal number and a base as command line arguments and output the decimal number in that specified base. For example: $ ./conv 13...

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#Assignment – 1
You are to write a simple C program that will take a decimal number and a base as command line arguments and output the decimal number in that specified base.
For example:
$ ./conv 13 2
1101
$ ./conv XXXXXXXXXX
716245
$ ./conv XXXXXXXXXX
843A91
$ ./conv XXXXXXXXXX
2J9Cu
$ ./conv XXXXXXXXXX
XXXXXXXXXX
$ ./conv
Usage: conv
ase
$ ./conv XXXXXXXXXX
INVALID BASE
(This is just example output, you should test against as many possible inputs as you can.)
Your program should be able to handle all bases from 2 to 64 and 256.
It must have 4 defined functions:
* int main(int argc, char *argv[]) (every C program must have this)
* void other_base(unsigned decimal, unsigned base) (for bases that are not a power of 2 or 256)
* void power2_base(unsigned decimal, unsigned base) (for bases that are a power of 2 but still not 256)
* void base_256(unsigned decimal, unsigned base) (for base 256 only)
Call only one of these functions during the execution of your program using the criteria given in parenthesis above.
Submit only the following files:
* Your conv.c source code file
Attempt to handle e
ors. See the example output for cases where no arguments are provided or an invalid base is given. Never trust user input.
Use a buffer of 32 characters. This will give you 31 locations for characters and the final location should be a null.
Remember: you have to put the digits into the buffer backwards and when the algorithm is finished, you have to printf() from the co
ect location in that buffer.
## Converting Integers to Characters
Think about how to use this character a
ay:
char *ascii = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz+/";
The character '1' is _not the same_ as the number 1. If you need to know which numeric values co
espond to which on screen characters, look at man ascii in your terminal.
## Division & Modulo
This algorithm is suitable for any base that is not a power of two and is not base 256 (other_base() function).
Let's see an example of converting the decimal number 29 into base 5. How many different values are there for base 5: 0, 1, 2, 3 and 4. So you should expect all of our digits to be one of those numbers. Get the first digit by calculating the remainder of 29 / 5:
__5
5| 29
XXXXXXXXXX
___
XXXXXXXXXX
The result of 29 / 5 is 5 with a remainder of 4.
There is a special operator for this in almost all programming languages: % (modulo) operator. This will give the remainder instead of the quotient.
29 % 5 = 4
This is the first digit (ones digit) of the base 5 number. To continue, you start from the quotient of this operation. Division in C is integer division (just like in Java), so the remainder is discarded when you do:
29 / 5 = 5
Now, continue with the algorithm:
__1
5| 5
XXXXXXXXXX
___
XXXXXXXXXX
The result of 5 / 5 is 1 with a remainder of 0.
5 % 5 = 0
This is the second digit (fives digit) of the base 5 number.
5 / 5 = 1
The algorithm continue until this division results in 0:
__0
5| 1
XXXXXXXXXX
___
XXXXXXXXXX
Now we have a remainder of 1 and the result of the integer division is 0.
The number 29 in base 5 is 104.
## Mask & Shift
This algorithm is suitable for any base that is a power of two and is not base 256 (power2_base() function).
What if you are trying to convert the number 7 into base 4? How many bit patterns are there for base 4: 00, 01, 10 and 11 which is 0, 1, 2 and 3. Let's see how masking works:
XXXXXXXXXX = 7
& 0011 = 3
__________
XXXXXXXXXX = 3
You've "masked off" the first digit, which is 3, by using the & (bitwise AND) operator. Now you can shift those bits to the right using the
(bitwise RIGHT SHIFT) operator like so:
7
2 = 01
And continue with the algorithm:
XXXXXXXXXX = 1
& 11 = 3
________
XXXXXXXXXX = 1
The number 7 in base 4 is 13.
## Base 256
This algorithm will only be used for base 256 (base_256() function).
It will involve using both previous algorithms. Since this is a power of 2, mask & shift must be utilized. However, the values you get will be numbers between 0 and 255. The ascii character a
ay doesn't have that many different characters in it, so instead you will represent base 256 numbers in the same format as IP addresses:
XXXXXXXXXX
Each place value is separated by a '.' character (period, dot). The division & modulo algorithm will be used to calculate each digit of the decimal number for each place value.
In the above example, the ones place shows the number 255 which would have been calculated using mask & shift from the input number. Then that value needs to be placed in the buffer as a three digit decimal number by using the division & modulo algorithm.
## Submission Format
Submit your solution as a file called conv.c along with a makefile that will compile it and output an executable called conv.
## Automated Tests ##
The automated tests for this assignment are the following:
**Compilation**
This test will simply test that your program builds when make is called.
**Invalid Input**
Your program should be able to handle cases where invalid input is passed to the program. In general, it is good practice to never trust user input.
You should catch the following cases:
**No Input**
If the program is run without any command line arguments, your program should detect it and report it by printing "Usage: ./conv
ase>". Print this string exactly. Also, make sure your program exits with a non-zero exit code. The exit code is set when you return in the main function.
Example:
$ ./conv
Usage: ./conv
ase
**Invalid Base**
If the user supplies a number for the base argument that is outside our supported range of XXXXXXXXXX, report it and exit with a non-zero exit code. Print "INVALID BASE" exactly.
Example:
$ ./conv XXXXXXXXXX
INVALID BASE
$ ./conv XXXXXXXXXX
INVALID BASE
**Invalid Number**
If the user supplies a non-number argument to the argument, print "INVALID NUMBER" exactly and exit with a non-zero exit code.
Example:
$ ./conv nan 14
INVALID NUMBER
**Power of 2 bases**
This test will test specifically bases 2, 4, 8, 16, 32, and 64. You should handle these bases specially in your program with the mask and shift method detailed above.
**Base 256**
This test will test specifically base 256.
**All Bases**
This test will test all other bases not tested above, possibly with some overlap (that is, base 4 might still get tested here too).

readme0-bkyyaqqr.md makefile0-kq2zvlfg dec0-xbytkzsy.c readme1-ot2jjf3n.docx conv1-a51fikbj.c

Answered 3 days After Dec 14, 2021

Solution

Shubham Kumar answered on Dec 17 2021

118 Votes

SOLUTION.PDF

#Assignment – 1 You are to write a simple C program that will take a decimal number and a base as command line arguments and output the decimal number in that specified base. For example: $ ./conv 13...

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