C - Pointers, arrays and strings
#TASKS
- 98 Battery st.
Write a function that takes a pointer to an int as parameter and updates the value it points to to 98.
Prototype: void reset_to_98(int *n);
- Don't swap horses in crossing a stream
Write a function that swaps the values of two integers.
Prototype: void swap_int(int *a, int *b);
- This report, by its very length, defends itself against the risk of being read
Write a function that returns the length of a string.
Prototype: int _strlen(char *s); FYI: The standard library provides a similar function: strlen. Run man strlen to learn more.
- I do not fear computers. I fear the lack of them
Write a function that prints a string, followed by a new line, to stdout.
Prototype: void _puts(char *str); FYI: The standard library provides a similar function: puts. Run man puts to learn more.
- I can only go one way. I've not got a reverse gear
Write a function that prints a string, in reverse, followed by a new line.
Prototype: void print_rev(char *s);
- A good engineer thinks in reverse and asks himself about the stylistic consequences of the components and systems he proposes
Write a function that reverses a string.
Prototype: void rev_string(char *s);
- Half the lies they tell about me aren't true
Write a function that prints every other character of a string, starting with the first character, followed by a new line.
Prototype: void puts2(char *str);
- Winning is only half of it. Having fun is the other half
Write a function that prints half of a string, followed by a new line.
Prototype: void puts_half(char *str); The function should print the second half of the string If the number of characters is odd, the function should print the last n characters of the string, where n = (length_of_the_string - 1) / 2
- Arrays are not pointers
Write a function that prints n elements of an array of integers, followed by a new line.
Prototype: void print_array(int *a, int n); where n is the number of elements of the array to be printed Numbers must be separated by comma, followed by a space The numbers should be displayed in the same order as they are stored in the array You are allowed to use printf
- strcpy
Prototype: char *_strcpy(char *dest, char *src); Write a function that copies the string pointed to by src, including the terminating null byte (\0), to the buffer pointed to by dest.
Return value: the pointer to dest FYI: The standard library provides a similar function: strcpy. Run man strcpy to learn more.
- Great leaders are willing to sacrifice the numbers to save the people. Poor leaders sacrifice the people to save the number Write a function that convert a string to an integer.
Prototype: int _atoi(char *s); The number in the string can be preceded by an infinite number of characters You need to take into account all the - and + signs before the number If there are no numbers in the string, the function must return 0 You are not allowed to use long You are not allowed to declare new variables of “type” array You are not allowed to hard-code special values We will use the -fsanitize=signed-integer-overflow gcc flag to compile your code. FYI: The standard library provides a similar function: atoi. Run man atoi to learn more.
- Don't hate the hacker, hate the code
Create a program that generates random valid passwords for the program 101-crackme.
You are allowed to use the standard library You don’t have to pass the betty-style tests (you still need to pass the betty-doc tests) man srand, rand, time gdb and objdump can help