5.c

#include 

int main(void)
{
	char a = 156;	//a是1个字节; unsigned : 0 - 255; signed : -128 - 127;
	printf("a = %d \n", a);
	a = 256;		//溢出;
	printf("a = %d \n", a);
	unsigned char c = 250;
	printf("c = %hhd \n", c);
//				 ^ 打印1个字节; 是有符号数; printf以什么格式输出;
	int s = -1;
	printf("s = %u \n", s);	// s = 4294967295
//				^ 无符号int;  -1 ==> 对应的是最大的无符号数;
//  负的2进制表示; -1 ==> 11111111 11111111 11111111 11111111
//	负数是以补码表示; ==> 00000000 00000000 00000000 00000000 + 1
//	-2 ==> 00000000 00000000 00000000 00000010 - 1 
//		   00000000 00000000 00000000 00000001
//		   11111111 11111111 11111111 11111110
	s = -2;
	printf("s = %u \n", s);	//s = 4294967294
	unsigned int i ;
	i = 4294967295;
	printf("i = %u i + 1 = %u i + 2 = %u \n", i, i+1,i+2);
	
	short ss = 30567;
	printf("ss = %hd \n", ss);	
	
	float ff = 0.2f;		//
	printf("ff = %f \n", ff);	//小数点后保留6位;
//	1 (符号位)  8(指数位)  23(小数位)
//  0 正 1 负 ; 

// 0.2 ==> 0.2 * 2 ==> 0.4  0
// 0.4 ==> 0.8				0
// 0.8 ==> 0.6 			    1
// 0.6 ==> 0.2              1
// ...................... ..0
//							0
//							1
//							1
//0.2 ==> 0.00110011001100110011....
//0.2 ==> 1.10011001100e-3

//	0    	127-3=124      100110011001 
//  0      01111100 	   1001100110011001100

	double db = 1.23;
//	1(符号位)	13(指数位)	50(小数)
	printf("db = %lf \n", db);
	
	int j = 96;
	printf("j = %d \n", j);
	printf("j = %#o \n", j);	
	printf("j = %#x \n", j);
//				 ^ 加前缀 ; 0 8进制; 0x 16进制;
	
}