C - Functions, nested loops

In this project, I learned about nested loops, header files, and variable scope in C while practicing declaring and defining my own functions.

Helper File 🙌

• _putchar.c: C function that writes a character to stdout.

Header File 📁

• main.h: Header file containing prototypes for all functions written in the project.

File	Prototype
1-alphabet.c	void print_alphabet(void);
2-print_alphabet_x10.c	void print_alphabet_x10(void);
3-islower.c	int _islower(int c);
4-isalpha.c	int _isalpha(int c);
5-sign.c	int print_sign(int n);
6-abs.c	int _abs(int);
7-print_last_digit.c	int print_last_digit(int);
8-24_hours.c	void jack_bauer(void);
9-times_table.c	void times_table(void)
10-add.c	int add(int, int);
11-print_to_98.c	void print_to_98(int n);
100-times_table.c	void print_times_table(int n)

Tasks 📃

• 0. _putchar

  • 0-holberton.c: C program that prints Holberton, followed by a new line. Returns 0.

• 1. I sometimes suffer from insomnia. And when I can't fall asleep, I play what I call the alphabet game

  • 1-alphabet.c: C function that prints the alphabet in lowercase, followed by a new line.

• 2. 10 x alphabet

  • 2-print_alphabet_x10.c: C function that prints the alphabet in lowercase 10 times, followed by a new line.

• 3. islower

  • 3-islower.c: C function that checks for lowercase characters. Returns 1 if the character is lowercase, 0 otherwise.

• 4. isalpha

  • 4-isalpha.c: C function that checks for alphabetic characters. Returns 1 if the character is a letter, 0 otherwise.

• 5. Sign

  • 5-sign.c: C function that prints the sign of a number. Returns:
    • 1 and prints + if the number is greater than zero.
    • 0 and prints 0 if the number is zero.
    • -1 and prints - if the number is less than zero.

• 6. There is no such thing as absolute value in this world. You can only estimate what a thing is worth to you

  • 6-abs.c: C function that returns the absolute value of an integer.

• 7. There are only 3 colors, 10 digits, and 7 notes; it's what we do with them that's important

  • 7-print_last_digit.c: C function that prints the last digit of a number. Returns the value of the last digit.

• 8. I'm federal agent Jack Bauer, and today is the longest day of my life

  • 8-24_hours.c: C function that prints every minute of the day of Jack Bauer, starting from 00:00 to 23:59.

• 9. Learn your times table

  • 9-times_table.c: C function that prints the 9 times table, starting with 0.

• 10. a + b

  • 10-add.c: C function that returns the addition of two integers.

• 11. School, 98 Battery Street, San Francisco CA 94111

  • 11-print_to_98.c: C function that prints all natural numbers from an input to 98 followed by a new line, as follows:
    • Numbers are separated by a comma followed by a space.
    • Numbers are printed in order.
    • Input represents the number to begin counting from.
    • 98 is the last number printed.

• 12. The World looks like a multiplication-table, or a mathematical equation, which, turn it how you will, balances itself

  • 100-times_table.c: C function that prints the times table of an input value, starting with 0:
    • If input is greater than 15 or less than 0, function prints nothing.

• 13. Nature made the natural numbers; All else is the work of women

  • 101-natural.c: C program that computes and prints the sum of all multiples of 3 or 5 below 1024 (excluded).

• 14. In computer class, the first assignment was to write a program to print the first 100 Fibonacci numbers. Instead, I wrote a program that would steal passwords of students. My teacher gave me an A

  • 102-fibonacci.c: C program that prints the first 50 Fibonacci numbers, starting with 1 and 2, followed by a new line. Numbers are separated by a comma followed by a space.

• 15. Even Liber Abbaci

  • 103-fibonacci.c: C program that prints the sum of even-valued Fibonacci numbers not exceeding 4,000,000, followed by a new line.

• 16. In computer class, the first assignment was to write a program to print the first 100 Fibonacci numbers. Instead, I wrote a program that would steal passwords of students. My teacher gave me an A+

  • 104-fibonacci.c: C program that prints the first 98 Fibonacci numbers, starting with 1 and 2, followed by a new line, without using long long, malloc, pointers, arrays, structures, or any library besides the standard. Numbers are separated by a comma followed by a space.