表达式必须具有常量值 [英] Expression must have a constant value

问题描述

我尝试了很多东西，但不知道如何修复它。

  int 大小; 
 cout<<输入   金额   客房 ： ; 
  cin >>尺寸; 
 
  const   int  x = size; 
  Point  * Room [x];  //  表达式必须具有常量值;  

解决方案

你不能这样做。你应该动态地分配内存。

 Point ** Room =  new 点* [大小]; 

BTW别忘了删除然后。

< blockquote>表达式在编译时必须是常量。您的代码使用运行时常量。编译时常量如下所示：

  const   int  x =  5 ; 
积分*房间[x];  //  好在这里 

创建一个数组在运行时，使用 new 运算符：

 Point * Room = 新点[size]; 
  //  在此使用空间 
  //   ...  
  //  完成后删除 
  delete  [] Room; 

注意到Carlo编辑了他的解决方案，使用指向 Point 的指针数组来使用与问题中的类型相同。我将保持我的例子不变，因为它可能是使用这种数组的意图。如果没有，应该使用Carlo的回答。

[/ EDIT]

I tried many things but didn''t know how to fix it.

int size;
cout<<" Enter The Amount of Rooms : ";
cin >> size;

const int x=size;
Point *Room[x]; //expression must have a constant value;

解决方案

You cannot do that. You should dynamically allocate memory instead.

Point **Room = new Point*[size]; 

BTW don''t forget to delete it then.

The expression must be constant at compile time. Your code uses a run-time constant. A compile time constant would look like this:

const int x = 5;
Point *Room[x]; // OK here

To create an array at runtime, use the new operator:

Point *Room = new Point[size];
// Use Room here
// ...
// Delete it when finished
delete [] Room;

[EDIT]
Noted that Carlo has edited his solution to use an array of pointers to Point to use the same types as in the question. I will left my example unchanged, because it may be the intention to use this kind of array. If not, Carlo''s answer should be used.
[/EDIT]

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