C语言 在 C 程序中使用 #define
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时间：2020-09-02 05:44:38 来源:igfitidea点击:
Using #define in C Program
提问by Oliver Spryn
I am trying to use #defineto define a constant in my program. I realize I could use const, but I am trying to get a good understanding of #define. Could someone please explain why the following code does not work, and should be done instead?
我试图#define在我的程序中定义一个常量。我意识到我可以使用const，但我试图很好地了解#define. 有人可以解释为什么下面的代码不起作用，而是应该这样做吗？
#include <stdio.h>
#define M 20;
typedef int Marray_t[M][M]; //I can't define an M x M array
int main() {
Marray_t A;
int i;
for (i = 0; i < M; ++i) { //Can't iterate up to M
A[i] = i;
}
return 0;
}
回答by nabroyan
You must remove ;after20, like this
你必须删除;after 20，像这样
#define M 20
