// Readability, probably introduced a bug or two, did not test it :)

void remove_dup(char target[], char other[])
{
	int out_index = 0;
	
	for(int i = 0; target[i] != '\0'; ++i)
	{
		if(!is_dup(target[i], other))
			target[out_index++] = target[i];	
	}

	target[out_index] = '\0';
}

bool is_dup(char targetChar, char other[])
{
		for(int j = 0; other[j] != '\0'; ++j)
			if(target[i] == other[j])
				return true;
	
	  return false;	  
}