strings_2.c

#include "main.h"
#include <stdlib.h>

/**
 * _isalpha - Check if Alphabetic
 *@c: Character
 * Return: 1 If True 0 If Not
 */
int _isalpha(int c)
{
	if (((c >= 97) && (c <= 122)) || ((c >= 65) && (c <= 90)))
		return (1);
	else
		return (0);
}

/**
 * _itoa - Convert Integer To Char
 * @n: Int To Convert
 * Return: Char Pointer
 */
char *_itoa(unsigned int n)
{
	int len = 0, i = 0;
	char *s;

	len = num_len(n);
	s = malloc(len + 1);
	if (!s)
		return (NULL);
	*s = '\0';
	while (n / 10)
	{
		s[i] = (n % 10) + '0';
		n /= 10;
		i++;
	}
	s[i] = (n % 10) + '0';
	array_rev(s, len);
	s[i + 1] = '\0';
	return (s);
}

/**
 * _pow - perform exponentiation
 * @base: base
 * @exponent: exponent
 * Return: Base raised to exponent
 */
int _pow(int base, int exponent)
{
	int ans = 1;

	while (exponent > 0)
	{
		int last_bit = (exponent & 1);

		if (last_bit)
			ans *= base;

		base *= base;
		exponent >>= 1;
	}
	return (ans);
}

/**
 * _atoi - convert strings to integers
 * @str: string to convert
 * Return: integer.
 */
int _atoi(const char *str)
{
	int j, i, n = 0, k = 1;
	char *tmp;

	if (str == NULL)
	{
		return (0);
	}

	tmp = _strdup(str);

	if (*str == '-')
	{
		*tmp = '0';
		k = -1;
	}
	i = _strlen(str);

	for (j = 0; j < i; ++j)
		n += (*(tmp + j) - '0') * _pow(10, i - j - 1);

	return (n * k);
}

/**
 * num_len - Determine Length Of number
 * @num: Given Int
 * Return: Length Of Int
 */
int num_len(int num)
{
	int len = 0;

	while (num != 0)
	{
		len++;
		num /= 10;
	}
	return (len);
}