c - get the last word (uppercase)

Question

I'm writing a code to print the last word in the string in uppercase and remove special characters or numbers if there is any, my code for now just print the last word how can I make it uppercase a remove any special characters

#include <stdio.h>
#include <unistd.h>

int main()
{
    char line[80] = "abc dfg, egh.";
    int i = 0, j;
    char *last_word;

    while (line[i] != '')
    {
        if (line[i] <= 32 && line[i + 1] > 32)
            last_word = &line[i + 1];
        i++;
    }
    i = 0;
    while (last_word && last_word[i] > 32)
    {
        write(1, &last_word[i], 1);
        i++;
    }
}

question from:https://stackoverflow.com/questions/65896866/get-the-last-word-uppercase

Answer 1

You need to add ctype.h library to use toupper function. I checked string character by character is an alphabetic character or not thanks to ASCII values the code is here:

#include <stdio.h>
#include <unistd.h>
#include <ctype.h> 

int main()
{
    char line[80] = "abc dfg, egh.";
    int i = 0, j;
    char *last_word;

    while (line[i] != '')
    {
        if (line[i] <= 32 && line[i + 1] > 32)
            last_word = &line[i + 1];
        i++;
    }
    i = 0;
    while (last_word && last_word[i] > 32)
    {
        if ((last_word[i] > 64 && last_word[i] <91) || (last_word[i]> 96 && last_word[i] < 123 ))
        printf("%c", toupper(last_word[i]));
        
        i++;
    }
}