== 1 ==
{{{
//strcpy

char* strcpy(char s1[], char s2[])
{
	int i = 0;
	while (*(s1 + i))
	{
		s1[i] = s2[i];
		i++;
	}
	return s1;
}
}}}
== 2 ==
{{{
//strlen

int strlen(char* p)
{
	int length = 0, i = 0;
	while (*(p + i)) {
		length++;
		i++;
	}
	return length;
}

}}}
== 3 ==
{{{
//strcat

void strcat(char s1[], char s2[])
{
	for (int i = strlen(s1); i < strlen(s1) + strlen(s2); i++)
	{
		s1[i] = s2[i];
	}
}

}}}
== 4 ==
{{{

}}}