如何将多维数组分配给临时变量？ [英] How to assign a multi-dimensional array to a temporary variable?

问题描述

我想将一个静态分配的多维数组分配给一个临时变量。考虑以下示例：

I want to assign a statically allocated, multi-dimensional array to a temporary variable. Consider the following example:

void foo(int b[3][2])
{
    b[1][1] = 1; // no segmentation fault
}

int main()
{
    int a[3][2] = {{1, 2}, {11, 12}, {21, 22}};

    foo(a);

    int** c;
    c = (int**)&a;
    c[1][1] = 1; // segmentation fault on execution

    int* d[3];
    d[0] = (int*)&(a[0]);
    d[1] = (int*)&(a[1]);
    d[2] = (int*)&(a[2]);
    d[1][1] = 1; // no segmentation fault

    return 0;
}

基本上我想做编译器对参数 b of foo（）。但是我唯一可以想到的工作解决方案是 d 。有没有更简单的方法？

Basically I want to do what the compiler does with the parameter b of foo(). But the only working solution I could come up with is d. Is there no less complicated way?

推荐答案

cdecl （手册页）是您的朋友：

cdecl> explain int b[3][2]
declare b as array 3 of array 2 of int
cdecl> declare b as pointer to array 2 of int
int (*b)[2]

所以，尝试这样：

void foo(int b[3][2])
{
    b[1][1] = 1; // no segmentation fault
}

int main()
{
    int a[3][2] = {{1, 2}, {11, 12}, {21, 22}};

    foo(a);

    int (*b)[2] = a;

    b[1][1] = 1;

    return 0;
}

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