COMPSCI 210
Part II
A4 Help
Part 1
Write a C function to print out a POSTIVE integer value in
base 4. (unsigned representation)
• Steps:
•
•
Read a number:
• Use _________
Write a method to print the number in base 4.
• Use a Loop to work out the value
• Example: 26 -> 122
• 26/4 => remainder: 2
• 6/4 => remainder: 2
• 1 (answer = 122)
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Part 1
Using redirection
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•
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Input file: only contain ONE positive number
Output: the number in base 4
You don’t need to change your source code.
Just run the code:
• Q1 < number1.txt
• Q1 < number2.txt
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Part 2 A
Write a C function that
• takes a parameter a character string of unknown length,
containing a single word
• translate this string from English into Pig Latin.
• move the first letter of the string, and append it onto the end
• concatenate the letters “ay”
• Assume that the array contains enough space for you to add the
extra characters.
char* toPLString(char * inputstring);
• Examples:
• Good -> oodGay
• Bad -> adBay
II-13-4
char* toPLString(char * inputstring);
Steps:
•
Input:
•
•
•
o
o
d
\0
o
o
d
G
a
the original string (pointer)
Output:
•
G
y
\0
The pointer
Task:
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•
•
•
•
•
•
•
Store the _______char
Copy the second char to the first char position and so on
Until the end of the string (______character)
Go back to the _______character
Put the _____character
Put 'a'
Put 'y'
Put the _____character
Return the pointer
II-13-5
Part 2 B
Write a program that reads a string from the keyboard and
displays it in Pig Latin
•Steps:
• Main method with arguments
• Number of arguments >=___ (_______, option)
• Use switch statement (note: must be integral type: char) Or if …
• Use atoi to change ASCII to Integer
• Assumption:
• size of the array = 7 including ay\0, total you can read = MAX
=4
• Text file only contain ONE line and one word
• Word with no more than 8 characters
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Case 1
Using getChar + while loop
• Input: the array to store the string
• Steps:
• Read each char using the getChar method and store the
character in the string
• Does it contain the newline character?
• Stop condition: \n or = ______
• Put the ____char at the end
• Output: return number of characters read
• Cases:
• Bad\n=> Bad\0
• Good\n => Good\0
• Hello\n => Hell\0
input
string
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Case 2
Using fgets
• Input: the array to store the string
• Steps:
• how many characters should you read? MAX=4
• Use fgets(buffer, _______, stdin) to read a string
• Does it contain newline character?
• Output: return number of characters read
• Cases:
• Bad\n=> Bad\n => Bad\0
• Good\n => Good => Good\0
• Hello\n => Hell => Hell\0
input
fgets
string
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Case 3
Using scanf
• Input: the array to store the string
• Steps:
• Use scanf to read a string
• Does it contain newline character?
• May overflow!
• Size of the array = 7,
• input: 8 chars -> CRASH
• Input <8 chars -> OK, but may overwrite values
• Take MAX characters only, set buffer[_____] to the null char
• Output: return number of characters read
• Cases:
• Bad\n=> => Bad\0
• Good\n => Good\0
• Hello\n => Hell\0
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Part 2
Using redirection
•
•
•
•
Input file: only contain ONE word and no more than 8 characters
Output: the string in Pig Latin
You don’t need to change your source code.
Just run the code:
• Q2 1 < input1.txt
• Q2 2 < input1.txt
• Q2 3 < input1.txt
II-13-10
Part 3
required to read all words from a text file and translate them
from English into Pig Latin.
• Assumption
• contains multiple lines
• one word per line.
• Size limit of each word to 128
• Steps:
• Declare a file pointer and open the text file
• Read a line at a time until the _____of the file
• Convert each word
• Display the answer
• close the file
• Examples:
• Q3 finput1.txt
• Q3 finput2.txt
II-13-11