rstr_capitalizer

Subject

Assignment name  : rstr_capitalizer
Expected files   : rstr_capitalizer.c
Allowed functions: write
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Write a program that takes one or more strings and, for each argument, puts
the last character that is a letter of each word in uppercase and the rest
in lowercase, then displays the result followed by a \n.

A word is a section of string delimited by spaces/tabs or the start/end of the
string. If a word has a single letter, it must be capitalized.

A letter is a character in the set [a-zA-Z]

If there are no parameters, display \n.

Examples:

$> ./rstr_capitalizer | cat -e
$
$> ./rstr_capitalizer "a FiRSt LiTTlE TESt" | cat -e
A firsT littlE tesT$
$> ./rstr_capitalizer "SecONd teST A LITtle BiT   Moar comPLEX" "   But... This iS not THAT COMPLEX" "     Okay, this is the last 1239809147801 but not    the least    t" | cat -e
seconD tesT A littlE biT   moaR compleX$
   but... thiS iS noT thaT compleX$
     okay, thiS iS thE lasT 1239809147801 buT noT    thE leasT    T$
$>

Commented solution

rstr_capitalizer

rstr_capitalizer.c

#include <unistd.h>

int ft_isspace(char c)
{
    if (c <= 32)
        return (1);
    return (0);
}

void ft_putchar(char c)
{
    write(1, &c, 1);
}

void r_capitalizer(char *s)
{
    int i = 0;
    while (s[i])
    {
         // If the character is uppercase, make it lowercase
         if (s[i] >= 'A' && s[i] <= 'Z')
             s[i] += 32;
         // Now check for lowercase character and if the next char
         // is a space character, make it uppercase again
         if ((s[i] >= 'a' && s[i] <= 'z') && ft_isspace(s[i + 1]))
             s[i] -= 32;
         // Now print every char
         ft_putchar(s[i++]);
    }
}

int main(int ac, char **av)
{
    int i = 1;
    if (ac == 1)
        ft_putchar('\n');
    else
    {
        // Loop over all params starting at 1 (we don't want the name of
        // the executable to be written to the screen)
        while (i < ac)
        {
            r_capitalizer(av[i]);
            ft_putchar('\n');
            i++;
        } 
    }
}