C Primer Plus（第六版）15.9 编程练习 第5题

//

//  main.c

//  15.9-5

//

//  Created by cjm on 2024/2/5.

//

#include <stdio.h>

#include <limits.h>

char * itobs(int n, char * ps);

unsigned int  rotate(unsigned int x,int i);

int main()

{

    unsigned int x=2999999999;

    printf("%u\n",rotate(x,3));//注意这里的打印格式

    return 0;

}

unsigned int rotate(unsigned int x,int i)

{

    unsigned int len;

    len = sizeof(unsigned int)*CHAR_BIT;

    char str[len+1];

    while(i!=0)

    {

        printf("旋转前    x=%s\n",itobs(x, str));

        printf("      x<<1=%s\n",itobs(x<<1, str));

        printf("x>>(len-1)=%s\n",itobs(x>>(len-1), str));

        x=x<<1|((x>>(len-1))&1);

        printf("旋转后    x=%s\n",itobs(x, str));

        i--;

    }

    return x;

}

char * itobs(int n, char * ps)

{

    int i;

    const static int size = CHAR_BIT * sizeof(int);

    for (i = size - 1; i >= 0; i--, n >>= 1)

    {

        ps[i] = (01 & n) + '0';

    }

    ps[size] = '\0';

    return ps;

}