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In C++, I can statically initialize an array, e.g.:
int a[] = { 1, 2, 3 };
Is there an easy way to initialize a dynamically-allocated array to a set of immediate values?
int *p = new int[3];
p = { 1, 2, 3 }; // syntax error
...or do I absolutely have to copy these values manually?
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Initializing dynamically allocated arrays. It's easy to initialize a dynamic array to 0. Syntax: int *array{ new int[length]{} };
We can create an array of pointers of size r. Note that from C99, C language allows variable sized arrays. After creating an array of pointers, we can dynamically allocate memory for every row.
Static array means the size of an array is static and dynamic array means the size of an array is dynamic. Once the array is created its size cannot be modified.
Static Memory Allocation is done before program execution. Dynamic Memory Allocation is done during program execution. In static memory allocation, once the memory is allocated, the memory size can not change. In dynamic memory allocation, when memory is allocated the memory size can be changed.
You can in C++0x:
int* p = new int[3] { 1, 2, 3 };
...
delete[] p;
But I like vectors better:
std::vector<int> v { 1, 2, 3 };
If you don't have a C++0x compiler, boost can help you:
#include <boost/assign/list_of.hpp>
using boost::assign::list_of;
vector<int> v = list_of(1)(2)(3);
You have to assign each element of the dynamic array explicitly (e.g. in a for or while loop)
However the syntax int *p = new int [3](); does initialize all elements to 0 (value initialization $8.5/5)
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