21 汉诺塔

#include <stdio.h>
char A, B, C;
han(int,  char, char, char);
main() {

    han(4, 'A', 'B', 'C');
}

han(n, A, B, C) {
    if (1 == n)
        printf("%d  %c-%c\n", n, A, C);
    else {
        han(n-1, A, B, C);
        printf("%d  %c-%c\n", n,A,C);
        han(n-1, B, A, C);
    }

}