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#include <stdio.h> | |
#include <stdlib.h> | |
int main(int argc, char *argv[]) { | |
// 看起来你是在x86_64上来跑的, int为4-bytes, 此时内存布局为: | |
// | |
// a[0] | |
// ↓ | |
// 96000000 fa000000 5e010000 c2010000 | |
int a[4] = {150, 250, 350, 450}; | |
int * c = a; | |
printf("1: a[0] = %d, a[1] = %d, a[2] = %d, a[3] = %d\n", a[0], a[1], a[2], a[3]); | |
// c | |
// ↓ | |
// 96000000 fa000000 5e010000 c2010000 | |
c = c + 1; | |
printf("current c points to %d\n", *c); | |
// | |
// c | |
// ↓ | |
// 96000000 fa000000 5e010000 c2010000 | |
c = (int *) ((char *) c + 1); | |
printf("%p\n", c); | |
// c | |
// ↓ | |
// 96000000 faf40100 00010000 c2010000 | |
// | |
// 最终: | |
// | |
// a[0] = 0x96 | |
// a[1] = 0x1f4fa -> 128250 | |
// a[2] = 0x100 -> 256 | |
// a[4] = 0x1c2 | |
*c = 500; | |
printf("2: a[0] = %d, a[1] = %d, a[2] = %d, a[3] = %d\n", a[0], a[1], a[2], a[3]); | |
} |
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