a[2]地址-a[0]地址 實際等於 (a[2]地址-a[0]地址)/a的類型 -- C

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#include <stdio.h>intmain(){int a[3] = {0x1,0x2,0x3};int *p, *q;printf("a[0] = 0x%X\n", a[0]);printf("a[1] = 0x%X\n", a[1]);printf("a[2] = 0x%X\n\n", a[2]);printf("&a[0] = 0x%X\n", &a[0]);printf("&a[1] = 0x%X\n", &a[1]);printf("&a[2] = 0x%X\n\n", &a[2]);p = &a[0];q = &a[2];printf("p = 0x%X\n", p);printf("q = 0x%X\n\n", q);/* q - p 實際運算是(q地址(0xBFE2097C) - p地址(0xBFE20984))/sizeof(int) */printf("q - p = 0x%X\n", q - p);printf("a[q - p] = 0x%X\n", a[q - p]);printf("a[&a[0] - &a[2]] = 0x%X\n", a[&a[2] - &a[0]]);}/*[[email protected] test_class]# ./a.out a[0] = 0x1a[1] = 0x2a[2] = 0x3&a[0] = 0xBFE2097C&a[1] = 0xBFE20980&a[2] = 0xBFE20984p = 0xBFE2097Cq = 0xBFE20984q - p = 0x2a[q - p] = 0x3a[&a[0] - &a[2]] = 0x3*/