/*
int	ft_is_alpha(char *ch)
{

	if (*ch >= 'a' && *ch <= 'z')
		return (1);	
	return (0);
}

int	ft_str_is_numeric(char *ch)
{
	if (*ch >= '0' && *ch <= '9')
		return (1);
	return (0);
}
*/
void	ft_strlowcase(char *str)
{
	int	i;

	i = 0;
	while(str[i] != '\0')
	{
		if ((str[i] >= 'A' && str[i] <= 'Z'))
		{
			str[i] += 32;
		}
		i++;
	}
}

void ft_strupcase(char *ch)
{
	if (*ch >= 'a' && *ch <= 'z')
	{
		*ch -= 32;
	}
}

char *ft_strcapitalize(char *str)
{
	int	i;
	int	start_of_word;

	i = 0;
	start_of_word = 1;
	ft_strlowcase(str);
	while(str[i] != '\0')
	{
		//if(ft_str_is_numeric(&str[i]) == 1)
        if(str[i]>= '0' && str[i] <= '9')
		{
			start_of_word = 0;
		}
        else if((str[i] >= 'a' && str[i] <= 'z') && start_of_word == 1 )
		//else if(ft_is_alpha(&str[i]) && start_of_word == 1 )
		{
			//ft_strupcase(&str[i]);
            if(str[i] >= 'a' && str[i] <= 'z')
                {str[i] -= 32;}
			start_of_word = 0;
		}
		else if (!(str[i] >= 'a' && str[i] <= 'z') && !(str[i] >= '0' && str[i] <= '9'))
		{
			start_of_word = 1;
		}
		i++;
	}
	
	return (str);
}

#include <stdio.h>
int main()
{
	char x[] = "salut, comment tu vas ? 42mots quarante-deux; cinquante+et+un";
	printf("%s \n", x);
	ft_strcapitalize(x);
	printf("%s", x);
}

Embed on website

To embed this project on your website, copy the following code and paste it into your website's HTML: