c语言中按位逻辑运算符、位移运算符

#include <stdio.h>

int count_bits(unsigned x)
{
    int bits = 0;
    while(x)
    {
        if(x & 1U)
            bits++;
        x >>= 1;
    }
    return bits;
}

int int_bits(void)
{
    return count_bits(~0U);
}

int print_bits(unsigned x)
{
    int i;
    for(i = int_bits() - 1; i >= 0; i--)
    {
        putchar(((x >> i) & 1U) ? ‘1‘ : ‘0‘);
    }
    putchar(‘\n‘);
}

int main(void)
{
    unsigned a, b;
    puts("please input two unsigned integers.");
    printf("unsigned a = "); scanf("%u", &a);
    printf("move unit  = "); scanf("%u", &b);
    
    printf("\nbinary a    = "); print_bits(a);
    printf("right move  = "); print_bits(a >> b);
    printf("left move   = "); print_bits(a << b);
    return 0;
}