sizeof(char)=1，但为何char类型的取值范围是-128～127？ sizeof(unsigned char)和sizeof(c...
\u5e2e\u6211\u89e3\u91ca\u4e0b\uff01\uff01 \u8c22\u8c22 \u8fd9\u662f\u6c42\u89e3\u6709\u7b26\u53f7char\u7c7b\u578b\u7684\u6700\u503c char a=8*sizeof(char)-1,b=1; b<<=a; \u8fd9\u4e24\u53e5\u4e0d\u660e\u767dchar a=8*sizeof(char)-1,b=1;
C\u8bed\u8a00\u91cc\uff0c\u89c4\u5b9asizeof\u8ba1\u6570\u7684\u662f\u5b57\u8282\uff0c\u4e00\u4e2a\u5b57\u8282\u5462\u5c31\u662f8\u4f4d\u4e8c\u8fdb\u5236\u6570\u3002
\u8fd9\u53e5\u8bdd\u5c31\u662f\u83b7\u5f97char\u7684\u4f4d\u6570\uff0c\u4e00\u822c\u4f4d\u6570\u4ece0\u5f00\u59cb\u8bb0\uff0c8\u4f4d\u5c31\u662f7\u4e86\uff0c\u7b2c8\u4f4d\u7684\u6743\u91cd\u5c31\u662f2\u76847\u6b21\u65b9\u3002
\u8fd9\u91cc\u5047\u8bbechar\u662f8\u4f4d\u4e8c\u8fdb\u5236\uff0c\u90a3\u4e48a\u5c31\u7b49\u4e8e7.
b<<=a;
b<<=a;\u5c31\u662fb = b<<a\uff1b\u5c31\u662fb\u7684\u503c\u53d8\u4f4db\u5de6\u79fba\u4f4d\u3002
\u4e5f\u5c31\u662f1\u5de6\u79fb7\u4f4d\uff0c\u4e8c\u8fdb\u5236\u4e3a10000000.
\u8fd9\u4e2a\u662f\u5e26\u7b26\u53f7\u7684\u6570\uff0c\u6700\u9ad8\u4f4d\u4e3a1\uff0c\u90a3\u4e48\u5c31\u662f\u8d1f\u6570\uff0c\u800c\u8d1f\u6570\u662f\u8865\u7801
\u6240\u4ee5\uff0c10000000\u53d6\u53cd\u540e\u5c31\u662f11111111\uff0c\u628a\u7b26\u53f7\u4f4d\u53bb\u4e86\u5c31\u662f01111111\u518d\u52a01\u5c31\u662f10000000\u5c31\u662f-128\u4e86\u3002
\u800c\u540e\u9762b=~b;
\u5c0610000000\u6309\u4f4d\u53d6\u53cd\uff0c\u5c31\u53d8\u6210\u4e8601111111\uff0c
\u6700\u9ad8\u4f4d\u4e3a\u7b26\u53f7\u4f4d\uff0c\u4e5f\u5c31\u662f+127.
\u90a3\u4e48char\u7684\u8303\u56f4\u5c31\u662f -128 ~ +127\uff08\u5047\u8bbechar\u4e3a8\u4f4d\uff0c\u6ce8\u610f\u8fd9\u91cc\u662f\u5e26\u7b26\u53f7\u7684\uff09.
\u5bf9\u4e8e\u4e0d\u540c\u7684\u8ba1\u7b97\u673a\u67b6\u6784\uff0c\u4e00\u4e2a\u5b57\u8282\u53ef\u80fd\u5305\u542b8\u4e2a\u6216\u8005\u66f4\u591a\u7684\u4f4d\uff0c\u5177\u4f53\u4e00\u4e2a\u5b57\u8282\u5305\u542b\u591a\u5c11\u4f4d\u4fdd\u5b58\u5728\u5b8fCHAR_BIT\u4e2d\u3002\u65e0\u8bba\u4e00\u4e2a\u5b57\u8282\u5305\u542b\u591a\u5c11\u4f4d\uff0cC++\u6807\u51c6\u89c4\u5b9a\uff1asizeof( unsigned char \uff09\u548csizeof( char )\u548csizeof( signed char \uff09\u603b\u662f\u7b49\u4e8e1\u3002
cppreference\u5173\u4e8esizeof( char )\u7684\u539f\u6587\uff1a
..楼主，sizeof()的值是字节数，1个字节是8位二进制啊。。
sizeof()是返回字节为单位的，一个字节8位
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绛旓細绛旀鏄 4 1 5
