Class Activities on 30 July 2021

These class activities are prepared in partial fulfillment of the requirements for the Software Development Practice I subject which is a part of computer engineering curriculum in King Mongkut’s University of Technology North Bangkok—KMUTNB—Thailand.

Task 7

Write a C program that

• creates a new file named data.txt (or overwrites it if there exists a file with the same name),
• randomizes up to N integer numbers (e.g. N=1000),
• saves the numbers to the file (one number per line),
• closes the file and exits the program.

Task 8

Write a C program that

• reads integer numbers from the text file data.txt up to N numbers,
• sorts the numbers using the Quicksort algorithm,
• saves the stored list of integers to the output file named data_sorted.txt.

Note: Write C code for the quicksort algorithm in the source file qsort.c and include it to your C project.

Task 9

Write a C program that behaves and produces the same output as the Python script given below:

# convert an integer to a hex string
def to_hex( value ):
    HEX_DIGITS = '0123456789abcdef'
    s = ''
    if (value < 0):
        value += (1 << 32)  # 32-bit value
    while True:
        d = HEX_DIGITS[ value & 0xf ]
        s = d + s
        value >>= 4
        if value == 0:
            break
    s = '0x' + s
    return s

if __name__ == "__main__": # some test code
    print (to_hex(33))  # 0x21
    print (to_hex(-1))  # 0xffffffff