c - 如何用 C 语言编写这些循环而不是使用#define？

Question

#define loop_x for (int x = 0; x < w; x++)
#define loop_y for (int y = 0; y < h; y++)
#define loop_xy loop_x loop_y

void game(int w, int h)
{
    unsigned univ[h][w];
    loop_xy univ[y][x] = rand() < RAND_MAX;
}

如何在不使用 #define 的情况下重写此代码？

Answer 1

所以你有:

#define loop_x for (int x = 0; x < w; x++)
#define loop_y for (int y = 0; y < h; y++)
#define loop_xy loop_x loop_y

void game(int w, int h)
{
    unsigned univ[h][w];
    loop_xy univ[y][x] = rand() < RAND_MAX;
}

首先将 loop_xy 解析为 loop_x loop_y:

    #define loop_x for (int x = 0; x < w; x++)
    #define loop_y for (int y = 0; y < h; y++)
    #define loop_xy loop_x loop_y

    void game(int w, int h)
    {
        unsigned univ[h][w];
        loop_x loop_y univ[y][x] = rand() < RAND_MAX;
    }

然后解析loop_x和loop_y:

    #define loop_x for (int x = 0; x < w; x++)
    #define loop_y for (int y = 0; y < h; y++)
    #define loop_xy loop_x loop_y

    void game(int w, int h)
    {
        unsigned univ[h][w];
        for (int x = 0; x < w; x++) for (int y = 0; y < h; y++) univ[y][x] = rand() < RAND_MAX;
    }