在一行中初始化矢量 [英] Initializing vectors in one line
问题描述
我正在使用STL中的vector类。通常，我逐个元素初始化值
，这非常不舒服，有时候不可能
（例如，当将常量向量传递给继承的构造函数时，因为我
在调用之前无法创建临时向量。
是否有可能在一行中分配一个向量，就像可能的那样
for数组？
我想写这样的代码：
#include< vector>
typedef std ::矢量< INT> ivec;
无效测试（ivec w）{};
int main（）{
//是否有可能制作这些线有效
//（例如通过扩展矢量类）？
ivec v = {1,2};
v = {3,4 };
test（{5,6}）;
返回0;
}
至少有一种解决方法可以调用
aconstructor（）：inheritedconstructor（{5,6}）{
...
}
其中inheritedconstructor需要一个向量？
请帮助，
Emanuel
" Emanuel Ziegler" < EZ ****** @ web.de>在消息中写道
news：c1 ********** @ news.urz.uni-heidelberg.de ...
我正在使用STL中的vector类。通常，我逐个元素地初始化值，这是非常不舒服的，有时是不可能的（例如，当将常量向量传递给继承的构造函数时，因为我在调用之前无法创建临时向量） 。
有可能在一行中分配一个向量，就像数组一样吗？
我想写这样的代码：
#include< vector>
typedef std :: vector< int> ivec;
void test（ivec w）{};
int main（）{
//是否有可能使这些行有效
//（例如通过扩展矢量类）？
ivec v = {1,2};
v = {3,4};
test（{5,6}）;
返回0; <是否至少有一种解决方法可以调用
aconstructor（）：inheritedconstructor（{5,6}）{
...
}
其中inheritedconstructor需要一个向量？
请帮助，
Emanuel
如何对这个？不需要新类型的向量。
#include< vector>
typedef std :: vector< int> ivec;
const int one_two [] = {1,2};
const int three_four [] = {3,4};
const int five_six [] = {5,6};
void test（ivec w）{};
int main（）{
ivec v（one_two，one_two + 2）;
v = ivec（three_four，three_four + 2）;
test（ivec（five_six， five_six + 2））;
返回0;
}
john
" Emanuel Ziegler" < EZ ****** @ web.de>在消息中写道
news：c1 ********** @ news.urz.uni-heidelberg.de ...
我正在使用STL中的vector类。通常，我逐个元素地初始化值，这是非常不舒服的，有时是不可能的（例如，当将常量向量传递给继承的构造函数时，因为我在调用之前无法创建临时向量） 。
有可能在一行中分配一个向量，就像数组一样吗？
我想写这样的代码：
#include< vector>
typedef std :: vector< int> ivec;
void test（ivec w）{};
int main（）{
//是否有可能使这些行有效
//（例如通过扩展矢量类）？
ivec v = {1,2};
v = {3,4};
test（{5,6}）;
返回0;
}
你应该看到所有的矢量构造函数。
这是一个演示代码 -
#include< vector>
#include< iostream>
使用命名空间std;
int main（）{
typedef vector< int> intVec;
intVec vec（10,5）;
intVec :: const_iterator it;
for（it = vec。 begin（）; it！= vec.end（）; it ++）
cout<< *它; //打印5次。
int arr [] = {1,2,3,4};
intVec vec2（arr，arr + 4 ）;
for（it = vec2.begin（）; it！= vec2.end（）; it ++）
cout<< *它; //打印1234
}
" John Harrison" <乔************* @ hotmail.com>在消息中写道
news：c1 ************* @ ID-196037.news.uni-berlin.de
这个怎么样？不需要新类型的矢量。
#include< vector>
typedef std :: vector< int> ivec;
const int one_two [] = {1,2};
const int three_four [] = {3,4};
const int five_six [] = {5 ，6};
void test（ivec w）{};
int main（）{
ivec v（one_two，one_two + 2）;
v = ivec（three_four，three_four + 2）;
测试（ivec（five_six，five_six + 2））;
返回0;
}
john
替代
v = ivec（three_four，three_four + 2）;
你也可以使用：
v.assign（three_four，three_four + 2）;
-
John Carson
1.要回复电子邮件地址，请删除donald
2.不要回复电子邮件地址（在此处发布）
Hi,
I am using the vector class from the STL. Normally, I initialize values
element by element, which is very uncomfortable and sometimes impossible
(e.g. when passing a constant vector to an inherited constructor, since I
cannot create a temporary vector before calling).
Is there a possibility to assign a vector in one line, like it is possible
for arrays?
I want to write code like this:
#include <vector>
typedef std::vector<int> ivec;
void test (ivec w) {};
int main () {
// Is there a possibility to make these lines valid
// (e.g. by extending the vector class)?
ivec v = {1, 2};
v = {3, 4};
test({5, 6});
return 0;
}
Is there at least a workaround for calling
aconstructor () : inheritedconstructor({5, 6}) {
...
}
where inheritedconstructor needs a vector?
Please help,
Emanuel
"Emanuel Ziegler" <ez******@web.de> wrote in message
news:c1**********@news.urz.uni-heidelberg.de...Hi,
I am using the vector class from the STL. Normally, I initialize values
element by element, which is very uncomfortable and sometimes impossible
(e.g. when passing a constant vector to an inherited constructor, since I
cannot create a temporary vector before calling).
Is there a possibility to assign a vector in one line, like it is possible
for arrays?
I want to write code like this:
#include <vector>
typedef std::vector<int> ivec;
void test (ivec w) {};
int main () {
// Is there a possibility to make these lines valid
// (e.g. by extending the vector class)?
ivec v = {1, 2};
v = {3, 4};
test({5, 6});
return 0;
}
Is there at least a workaround for calling
aconstructor () : inheritedconstructor({5, 6}) {
...
}
where inheritedconstructor needs a vector?
Please help,
Emanuel
How about this? No need for a new type of vector.
#include <vector>
typedef std::vector<int> ivec;
const int one_two[] = { 1, 2 };
const int three_four[] = { 3, 4 };
const int five_six[] = { 5, 6 };
void test (ivec w) {};
int main () {
ivec v(one_two, one_two + 2);
v = ivec(three_four, three_four + 2);
test(ivec(five_six, five_six + 2));
return 0;
}
john
"Emanuel Ziegler" <ez******@web.de> wrote in message
news:c1**********@news.urz.uni-heidelberg.de...Hi,
I am using the vector class from the STL. Normally, I initialize values
element by element, which is very uncomfortable and sometimes impossible
(e.g. when passing a constant vector to an inherited constructor, since I
cannot create a temporary vector before calling).
Is there a possibility to assign a vector in one line, like it is possible
for arrays?
I want to write code like this:
#include <vector>
typedef std::vector<int> ivec;
void test (ivec w) {};
int main () {
// Is there a possibility to make these lines valid
// (e.g. by extending the vector class)?
ivec v = {1, 2};
v = {3, 4};
test({5, 6});
return 0;
}
You should probably see all the vector constructors.
Here is a demo code -
#include <vector>
#include <iostream>
using namespace std;
int main(){
typedef vector<int> intVec;
intVec vec(10, 5);
intVec::const_iterator it;
for( it=vec.begin(); it!=vec.end(); it++)
cout << *it; // Print 5 ten times.
int arr[]={1, 2, 3, 4};
intVec vec2(arr, arr+4);
for( it=vec2.begin(); it!=vec2.end(); it++)
cout << *it; // Print 1234
}
"John Harrison" <jo*************@hotmail.com> wrote in message
news:c1*************@ID-196037.news.uni-berlin.de
How about this? No need for a new type of vector.
#include <vector>
typedef std::vector<int> ivec;
const int one_two[] = { 1, 2 };
const int three_four[] = { 3, 4 };
const int five_six[] = { 5, 6 };
void test (ivec w) {};
int main () {
ivec v(one_two, one_two + 2);
v = ivec(three_four, three_four + 2);
test(ivec(five_six, five_six + 2));
return 0;
}
john
As an alternative to
v = ivec(three_four, three_four + 2);
you can also use:
v.assign(three_four, three_four + 2);
--
John Carson
1. To reply to email address, remove donald
2. Don''t reply to email address (post here instead)
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