循环移位

[c]代码库

/* 循环移位 */
#include <stdio.h>

void print_bin(const int a, const int size) {
	unsigned flag = 1 << (size * 8 - 1);

	while (flag != 0) {
		printf("%d", 0 != (a & flag));
		flag >>= 1;
	}
}

unsigned cycclic_right_shift(unsigned a, int n) {
	unsigned b = 0;
	int size = sizeof(unsigned) * 8;
	n %= size;

	b = a << (size - n);
	a = a >> n;
	a |= b;

	return a;
}

int main(void) {
	int size = 0;
	int a = 0;
	int n = 0;

	printf("a = ");
	scanf("%d", &a);
	printf("n = ");
	scanf("%d", &n);

	print_bin(a, sizeof(unsigned));
	printf("\n");

	a = cycclic_right_shift(a, n);

	print_bin(a, sizeof(unsigned));
	printf("\n");

	return 0;
}