c05 - KimTaebin-ai/study_posts GitHub Wiki

int	ft_iterative_factorial(int nb)
{
	int	result;
	int	i;

	i = 2;
	result = 1;
	if (nb < 0)
	{
		return (0);
	}
	else if (nb == 1)
	{
		return (1);
	}
	while (i <= nb)
	{
		result *= i++;
	}
	return (result);
}

int	ft_recursive_factorial(int nb)
{
	if (nb < 0)
	{
		return (0);
	}
	else if (nb < 2)
	{
		return (1);
	}
	return (nb * ft_recursive_factorial(nb - 1));
}

int	ft_iterative_power(int nb, int power)
{
	int	i;
	int	result;

	i = 1;
	result = nb;
	if (nb < 0)
	{
		return (0);
	}
	else if (nb == 0 && power == 0)
	{
		return (1);
	}
	else
	{
		while (i <= power)
		{
			result += nb;
			i++;
		}
	}
	return (result);
}

int	ft_recursive_power(int nb, int power)
{
	if (nb < 0)
	{
		return (0);
	}
	else if (power == 0)
	{
		return (1);
	}
	else if (nb == 0)
	{
		return (0);
	}
	return (nb * ft_recursive_power(nb, power - 1));
}

int	ft_fibonacci(int index)
{
	if (index < 0)
		return (-1);
	else if (index == 0)
		return (0);
	else if (index == 1)
		return (1);
	return (ft_fibonacci(index - 1) + ft_fibonacci(index - 2));
}

#include <stdio.h>

int ft_sqrt(int nb) 
{
    int i;
    int sqrt;

    i = 0;
    sqrt = 0;
    if (nb < 1)
        return 0;
    while (1) {
        sqrt = i * i;
        if (sqrt == nb)
            return i;
        else if (sqrt > nb)
            return 0;
        i++;
    }
}

#include <stdio.h>

int ft_is_prime(int nb) {
    // 2부터 실행 ~ 자기 자신 - 1
    // nb % i == 0
    int i = 2;
    int is_prime = 1;
    if (nb <= 2) {
        return is_prime;
    } 
    while (i < nb) {
        if (nb % i == 0) {
            is_prime = 0;
        }
        i++;
    }
    return is_prime;
}

int	is_prime(int num)
{
	long	i;
	long	prime;

	i = 2;
	if (num <= 1)
		return (0);
	if (num == 2)
		return (1);
	while (1)
	{
		if (num % i == 0)
			return (0);
		prime = i * i;
		if (prime > num)
			break ;
		i++;
	}
	return (1);
}

int	ft_find_next_prime(int nb)
{
	int	num;

	num = nb;
	while (1)
	{
		if (is_prime(num))
			return (num);
		num++;
	}
}

#include <unistd.h>

void	print_arr(int *arr)
{
	int		i;
	char	c;

	i = 0;
	while (i < 10)
	{
		c = arr[i] + '0';
		write(1, &c, 1);
		i++;
	}
	write(1, "\n", 1);
}

int	check(int col, int *arr)
{
	int	i;

	i = 0;
	while (i < col)
	{
		if (arr[i] == arr[col])
			return (0);
		if (arr[i] - arr[col] == i - col)
			return (0);
		if (arr[i] - arr[col] == col - i)
			return (0);
		i++;
	}
	return (1);
}

int	check_queen(int col, int *arr)
{
	int	i;
	int	count;

	i = 0;
	count = 0;
	if (col == 10)
	{
		print_arr(arr);
		return (1);
	}
	while (i < 10)
	{
		arr[col] = i;
		if (check(col, arr))
			count += check_queen(col + 1, arr);
		i++;
	}
	return (count);
}

int	ft_ten_queens_puzzle(void)
{
	int	arr[10];
	int	i;
	int	result;

	i = 0;
	result = 0;
	while (i < 10)
		arr[i++] = 0;
	i = 0;
	while (i < 10)
	{
		result += check_queen(1, arr);
		arr[0]++;
		i++;
	}
	return (result);
}