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这题哪错了？

这题哪错了？# JobHunting - 待字闺中

h*g2011-03-21 07:03

1 楼

int fun(int **p);
a[3][3];
fun(a);
what's the problem？

C*y2011-03-21 07:03

2 楼

指针类型不对
可以int fun(int p[][3])

【在 h*****g 的大作中提到】

: int fun(int **p);
: a[3][3];
: fun(a);
: what's the problem？

Z*42011-03-21 07:03

3 楼

或者写
int fun(int *p[3])应该也行

C*y2011-03-21 07:03

4 楼

应该是int fun(int (*p)[3])吧

【在 Z**********4 的大作中提到】

: 或者写
: int fun(int *p[3])应该也行

h*g2011-03-21 07:03

5 楼

这样也可以吧？
int fun(int *p);
a[3][3];
fun(*a);

【在 C***y 的大作中提到】

: 指针类型不对
: 可以int fun(int p[][3])

j*y2011-03-21 07:03

6 楼

如果能写成这样，那么就可以写成int fun(int **p)了。
记得int main(int argc, char *argv[])也可以写成int main(int argc, char **argv)
Chevy提供的是正确的用法。
相似的例子在K&R的书上也有：
If a two-dimensional array is to be passed to a function, the parameter
declaration in the function must include the number of columns; the number
of rows is irrelevant, since what is passed is, as before, a pointer to an
array of rows, where each row is an array of 13 ints. In this particular
case, it is a pointer to objects that are arrays of 13 ints. Thus if the
array daytab is to be passed to a function f, the declaration of f would be:
f(int daytab[2][13]) { ... }
It could also be
f(int daytab[][13]) { ... }
since the number of rows is irrelevant, or it could be
f(int (*daytab)[13]) { ... }
which says that the parameter is a pointer to an array of 13 integers. The
parentheses are necessary since brackets [] have higher precedence than *.
Without parentheses, the declaration
int *daytab[13]
is an array of 13 pointers to integers. More generally, only the first
dimension (subscript) of an array is free; all the others have to be
specified.

【在 Z**********4 的大作中提到】

: 或者写
: int fun(int *p[3])应该也行

n*02011-03-21 07:03

7 楼

fun的声明里说p是一个“pointer to a pointer to an integer”
编译器处理fun（a）调用的时候会把a的l-value（也就是a的首地址，也就是“pointer
to an integer”）传给fun。
所以这里出现了类型的不匹配。

【在 h*****g 的大作中提到】

: int fun(int **p);
: a[3][3];
: fun(a);
: what's the problem？