#include<stdio.h>
int main()
{
	int a = 5;
	int b = !a;
	printf("%d", b);
	return 0;
}


sizeof 的使用


int main()
{
	int arr[10] = {0};
	char ch = 0;
	printf("%d\n", sizeof (int[10]));
	printf("%d", sizeof(ch));

	return 0;
}



按位取反~


int main()
{
	int a = -1;
	int b = ~a;
	printf("%d", b);
	return 0;
}



把a二级制中第五位改变成1，又改变成0；
int main()
{
	int a = 13;
	int b = a | (1 << 4);
	int c = a & ~(1 << 4);
	printf("%d %d", b, c);
	return 0;
	

}