C语言学习4-1： 汉若塔。10进制装二进制，8进制，16进制。杨辉三角。

1.。。。。。。。。。。。。。。。。。。。。

#include <stdio.h>

void hanoi(char from, char pass, char to, unsigned n)
{
    if (n == 1)
    {
        printf("%c ==> %c
", from, to);    
    }
    else
    {
        hanoi(from, to, pass, n - 1);    
        hanoi(from, pass, to, 1);
        hanoi(pass, from, to, n - 1);
    }
}

void hanoi1(char from, char pass, char to, unsigned n)
{
    if (n == 0)
        return;
    hanoi(from, to, pass, n - 1);
    printf("%c ==> %c
", from, to);
    hanoi(pass, from, to, n - 1);
}

int main(void)
{
    unsigned n;

    printf("pls input n: ");
    scanf("%d", &n);

    hanoi1('A', 'B', 'C', n);

    return 0;
}

2.。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。

#include <stdio.h>

void __foo(unsigned n, unsigned radix)
{
    unsigned q, r;
    static level;

    if (n <= 0)
        return;

    r = n % radix;
    q = n / radix;

    level++;
    __foo(q, radix);
    level--;

    if (r > 9)
        putchar(r - 10 + 'a');
    else
        putchar(r + '0');

    if (level % 4 == 0)
        putchar(' ');
}

void foo(unsigned n, unsigned radix)
{
    if (n == 0)
    {
        printf("0
");
        return;
    }

    if (radix != 2 && radix != 8 && radix != 16)
        return;

    if (radix == 16)
        printf("0x");
    else if (radix == 8)
        printf("o");
    else
        printf("0b");

    __foo(n, radix);

    putchar('
');
}

int main(void)
{
    unsigned n, base;

    printf("input n & base: ");
    scanf("%d%d", &n, &base);

    printf("transformed: ");
    foo(n, base);

    return 0;
}

level是用来分四个四个的

3，。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。

#include <stdio.h>

unsigned yh_triangle(unsigned row, unsigned col)
{
    if (col == 1 || row == col)
        return 1;

    return yh_triangle(row - 1, col - 1) + yh_triangle(row - 1, col);
}

int main(void)
{
    unsigned n;

    printf("input n: ");
    scanf("%d", &n);

    int i, j;
    for (i = 1; i <= n; i++)
    {
        for (j = 1; j <= i; j++)    
        {
            printf("%4d ", yh_triangle(i, j));    
        }
        putchar('
');
    }

    return 0;
}

结果：

input n: 6
   1
   1    1
   1    2    1
   1    3    3    1
   1    4    6    4    1
   1    5   10   10    5    1