README.md

0x02. C - Functions, nested loops

Learning objectives for this project:

• What are nested loops and how to use them
• What is a function and how do you use functions
• What is the difference between a declarartion and a definition of a function
• What is a prototype
• Scope of variables
• What are the gcc flags -Wall -Werror -pendatic -Wextra -std=gnu89
• What are header files and how to use them with #include

Tests ✔️

• Tests: Location of test files. Provided by Holberton School.

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 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-putchar.c: C program that prints _putchar, followed bby a new line.
    • The program should return 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 program that prints the alphabet in lowercase, followed by a new line
    • Prototype: coid print_alphabet(void);
    • You can only use _putchar twice in our code

• 2. 10 x alphabet

  • 2-print_alphabet_x10.c: C program that prints 10 times the alphabet, in lowercase, followed by a new line.
    • Prototype: void print_alphabet_x10(void);
    • You can only use _putchar twice in your code

• 3. islower

  • 3-islower.c: C program that checks for lowercase character.
    • Prototype: int _islower(int c);
    • Returns 1 if c is lowercase
    • Returns 0 otherwise.

• 4. isalpha

  • 4-isalpha.c: C program that checks for alphabetic character.
    • Prototype: int _islpha(int c);
    • Returns 1 if c is a letter, lowercase or uppercase
    • Returns 0 otherwise

• 5. Sign

  • 5-sign.c: C program that prints the sign of number
    • Prototype: int print_sign(int n);
    • Returns 1 and prints + if n is greater than zero
    • Returns 0 and prints 0 if n is zero
    • Returns -1 and prints - if n 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 program that computes the absolute value of an integer
    • Prototype: int _abs(int);

• 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 program prints the last digit of a number.
    • Prototype: int print_last_digit(int);
    • 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 program that prints every minute of the day of Jack Bauer, starting from 00:00 to 23:59.
    • Prototype: void jack_bauer(void);
    • You can listen this soundtrack while coding :)

• 9. Learn your times table

  • 9-times_table.c: C program that prints the 9 times table, starting with 0.
    • Prototype: void times_table(void);

• 10. a + b

  • 10-add.c: C program that adds two integers and returns the result - Prototype: int add(int, int);

• 11. 98 Battery Street, the OG

  • 11-print_to_98.c: C program that prints all natural numbers from n to 98, followed by a new line.
    • Prototype: void print_to_98(int n);
    • Numbers must be separated by a comma, followed by a space
    • Numbers should be printed in order
    • The first printed number should be the number passed to your function.
    • The last printed number should 98
    • You are allowed to use the standard library

• 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 program that prints the n times table, starting with 0.
    • Prototype: void print_times_table(int n);
    • If n is greater than 15 or less than 0 the function should not print anything

• 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 the multiples of 3 or 5below 1024 (excluded), followed by a new line.
    • You are allowed to use the standard library

• 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 Fibonnaci numbers, strting with 1and 2, followed by a new line.
    • The numbers must be separated by comma, followed by a space ,
    • You are allowed to use the standard library

• 15. Even Liber Abbaci

  • 103-fibonacci.c: C program that prints the sum of even-valued terms less than 4,000,000 as in the Fibonnaci sequence, 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 finds and prints the first 98 Fibonnaci numbers, starting with 1 and 2, followed by a new line.
    • The numbers should be separated by comma, followed by a space ,
    • You are allowed to use the standard library
    • You are not allowed to use any other library (You can’t use GMP etc…)
    • You are not allowed to use long long, malloc, pointers, arrays/tables, or structures
    • You are not allowed to hard code any Fibonacci number (except for 1 and 2)