【递归】汉诺塔的递归与非递归（压栈）

#include <stdio.h>

struct stack
{
    int n;
    char x, y, z;
}sta[200];



void hanoi(int n, char a, char b, char c);
void hanoiStack(int n, char fr, char to, char by);

int main(void)
{
    int n;
    printf("How many hanoi TOWERS?\n");
    
    for(int loop = 0; loop < 200; loop++)
    {
        sta[loop].n = 0;
        sta[loop].x = ‘0‘;
        sta[loop].y = ‘0‘;
        sta[loop].z = ‘0‘;
    }
    
    scanf("%d", &n);
    hanoiStack(n, ‘a‘, ‘b‘, ‘c‘);
    return 0;
}
void hanoi(int n, char a, char b, char c)
{
    if(n == 1)
        printf("%c --> %c\n", a, c);
    else
    {
        hanoi(n - 1, a, c, b);
        printf("%c --> %c\n", a, c);
        hanoi(n - 1, b, a, c);
    }
}
void hanoiStack(int n, char fr, char to, char by)
{
    int top = 1, n1, a, b, c;

    sta[top].n = n; 
    sta[top].x = fr; 
    sta[top].y = by; 
    sta[top].z = to;

    while(top > 0)
    {
        n1 = sta[top].n;
        a = sta[top].x;
        b = sta[top].y;
        c = sta[top].z;
        top--;
        
        // 下面压栈
        if(n1 > 1)
        {
            top++;
            sta[top].n = n1 - 1;
            sta[top].x = b;
            sta[top].y = c;
            sta[top].z = a;
            
            top++;
            sta[top].n = 1;
            sta[top].x = a;
            sta[top].z = c;
            
            top++;
            sta[top].n = n1 - 1;
            sta[top].x = a;
            sta[top].y = c;
            sta[top].z = b;

        }
        else
        {
            printf("\nmove from %c to %c ", a, c);
        }
    }
}