33 lines
628 B
C
33 lines
628 B
C
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#include <stdio.h>
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#include <string.h>
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#include <stdlib.h>
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struct
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{
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unsigned char a : 2;
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unsigned char : 1; // 占位符
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unsigned char b : 2;
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unsigned char : 1; // 占位符
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unsigned char c : 2;
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} REG;
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int main()
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{
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REG.a = 3;
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REG.b = 1;
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REG.c = 2;
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printf("%ld B\n", sizeof(REG)); // 1 B
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char reg = *((char *)®); // 原理: 位段的内存存储是从低位到高位的
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printf("%#hhx\n", reg); // 0x11
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// 打印二进制
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printf("reg = 0b");
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for (int i = 7; i >= 0; i--)
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{
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printf("%d", (reg >> i) & 1);
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}
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printf("\n");
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return 0;
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}
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