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原标题:array of pointers
  • 时间:2010-04-20 18:13:37
  •  标签:
  • c++
  • pointers
char *a[]={"diamonds","clubs","spades","hearts"};
char **p[]={a+3,a+2,a+1,a};
char ***ptr=p;
cout<<*ptr[2][2];

为什么会显示,请解释2个tr执行阵列及其内容。

最佳回答

请注意,x[y]对条码的紧接于<条码>*x,因此,<条码>*ptr (2) 被解释为<条码>*(ptr (2)]。

还注意到x[y]=*(x+y)

因此,

*(ptr[2][2]) == *(p[2][2])    // ptr = p
             == *((a+1)[2])   // p[2] == a+1
             == *(*(a+1+2))   // x[y] == *(x+y)
             == *(*(a+3))     // 1+2 == 3
             == *(a[3])       // *(x+y) == x[y]
             == *("hearts")   // a[3] == "hearts"
             == "hearts"[0]   // *x == *(x+0) == x[0]
             ==  h 
问题回答

见KennyTM对解释的出色回答......但我认为,这是教授利用你的夸张来“视像”记忆的完美例子。

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