问题描述
我有一个函数 foo(int[] nums)，我理解它本质上等同于 foo(int* nums).在 foo 内部，我需要将 nums 指向的数组的内容复制到 范围内声明的一些 .我理解以下内容无效:int[10] 中富
I have a function foo(int[] nums) which I understand is essentially equivalent to foo(int* nums). Inside foo I need to copy the contents of the array pointed to by numsinto some int[10] declared within the scope of foo. I understand the following is invalid:
void foo (int[] nums)
{
myGlobalArray = *nums
}
复制数组的正确方法是什么?我应该像这样使用 memcpy:
What is the proper way to copy the array? Should I use memcpy like so:
void foo (int[] nums)
{
memcpy(&myGlobalArray, nums, 10);
}
还是应该使用 for 循环?
or should I use a for loop?
void foo(int[] nums)
{
for(int i =0; i < 10; i++)
{
myGlobalArray[i] = nums[i];
}
}
我还缺少第三种选择吗?
Is there a third option that I'm missing?
推荐答案
Memcpy 可能会更快，但使用它的可能性更大.这可能取决于您的优化编译器的智能程度.
Memcpy will probably be faster, but it's more likely you will make a mistake using it. It may depend on how smart your optimizing compiler is.
您的代码不正确.应该是:
Your code is incorrect though. It should be:
memcpy(myGlobalArray, nums, 10 * sizeof(int) );
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