blocks|key|879714|text|是的，但是你必须使用std::copy算法：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|879715|#include+<iostream>
#include+<iterator>
#include+<vector>

int+main()
{
++++std::vector<int>+a;
++++//+fill+a...
++++std::copy(a.begin(),+a.end(),+std::ostream_iterator<int>(std::cout));
}|code-block|syntax|javascript|879716|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

Yep, but you must use std::copy algorithm:

<pre><code>#include &lt;iostream&gt;
#include &lt;iterator&gt;
#include &lt;vector&gt;

int main()
{
 std::vector&lt;int&gt; a;
 // fill a...
 std::copy(a.begin(), a.end(), std::ostream_iterator&lt;int&gt;(std::cout));
}
</code></pre>

blocks|key|1094461|text|另一种选择-+Boost.Lambda。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|1094462|for_each(v.begin(),+v.end(),+cout+<<+boost::lambda::_1);|code-block|syntax|javascript|1094463|entityMap|0|LINK|mutability|MUTABLE|url|http://www.boost.org/doc/libs/1_44_0/doc/html/lambda/using_library.html^0|7|C|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@$A|R|B|S|1|T]]|C|$]]|$1|D|3|E|5|F|7|U|8|@]|9|@]|C|$G|H]]|$1|I|3|-4|5|6|7|V|8|@]|9|@]|C|$]]]|J|$K|$5|L|M|N|C|$O|P]]]]

Another option — <a href="http://www.boost.org/doc/libs/1_44_0/doc/html/lambda/using_library.html" rel="noreferrer">Boost.Lambda</a>.

<pre><code>for_each(v.begin(), v.end(), cout &lt;&lt; boost::lambda::_1);
</code></pre>

blocks|key|879759|text|在公司代码中并不总是合适的，但为了枚举选项-如果你真的发现其他for_each+/+std::copy等解决方案太过冗长，你可以写：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|879760|std::ostream&+operator(std::ostream&+os,+const+std::vector<My_Type>&+v)
{
+++++//+pick+one+of+the+other+implementations+for+here...
++++std::copy(std::istream_iterator<My_Type>(os),+std::istream_iterator<My_Type>(),+++
++++++++++std::back_inserter(v_Numbers));+++
}|code-block|syntax|javascript|879761|如果你足够有礼貌(;-p)，只重载你特定的向量实例化(这需要My_Type不仅仅是一个类型定义函数来表示int，尽管创建一个模板类来创建包装任意类型的新类型并不难)，那就更好了。否则，如果其他人在您的翻译单元中的其他地方执行相同的操作，流可能会变得不明确。|879762|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

Not always appropriate in corporate code, but for the sake of enumerating options - if you really find other for_each / std::copy etc. solutions too verbose, you could write:

<pre><code>std::ostream&amp; operator(std::ostream&amp; os, const std::vector&lt;My_Type&gt;&amp; v)
{
 // pick one of the other implementations for here...
 std::copy(std::istream_iterator&lt;My_Type&gt;(os), std::istream_iterator&lt;My_Type&gt;(), 
 std::back_inserter(v_Numbers)); 
}
</code></pre>

It's much nicer if you're well-mannered (;-p) enough to only overload your specific instantiation of vector (which requires My_Type be more than a typedef to say int, though it's not hard to create a templated class to create new types wrapping an arbitrary type). Otherwise, if someone else does the same elsewhere in your translation unit, the streaming could become ambiguous.

blocks|key|1094572|text|是的，使用lambda表达式(+STL+11)，我们可以将C%2B%2B容器的每个元素内联打印到cout。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1094573|#include+<iostream>+++//+cout
#include+<vector>+++++//+vector
#include+<algorithm>++//+for_each
#include+<iterator>+++//+istream_iterator
using+namespace+std;

int+main()
{
+++std::vector<int>+v(10,2);
+++std::for_each(v.begin(),+v.end(),+[](int+i)->void+{std::cout+<<+i+<<endl;});
+++return+0;
}|code-block|syntax|javascript|1094574|为了从cin到向量读取"n“值，|1094575|+int+main()
+{
+++std::vector<int>+v;

+++int+elementsToRead;
+++cin>>elementsToRead;++//+Number+of+elements+to+copy

+++//+Reading+from+istream
+++std::istream_iterator<int>+ii2(std::cin);
+++std::copy_n(ii2,+elementsToRead,+std::back_inserter(v));

+++//+printing+updated+vector
+++std::for_each(v.begin(),+v.end(),+[](int+i)->void+{cout+<<+i+<<endl;});

+++return+0;
}|1094576|(或)使用Lambda表达式|1094577|std::for_each(std::istream_iterator<int>(cin),std::istream_iterator<int>(),[&v](int+i)->void+{+v.push_back(i);});|1094578|要了解有关Lambda+expression+@+What+is+a+lambda+expression+in+C%2B%2B11?的更多信息|offset|length|1094579|entityMap|0|LINK|mutability|MUTABLE|url|https://stackoverflow.com/questions/7627098/what-is-a-lambda-expression-in-c11^0|0|0|0|0|0|0|P|11|0|0^^$0|@$1|2|3|4|5|6|7|10|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|11|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|12|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|13|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|14|8|@]|9|@]|A|$]]|$1|M|3|N|5|D|7|15|8|@]|9|@]|A|$E|F]]|$1|O|3|P|5|6|7|16|8|@]|9|@$Q|17|R|18|1|19]]|A|$]]|$1|S|3|-4|5|6|7|1A|8|@]|9|@]|A|$]]]|T|$U|$5|V|W|X|A|$Y|Z]]]]

yup, using lambda expression (C++ 11) we can inline printing of each element of a STL container to cout.

<pre><code>#include &lt;iostream&gt; // cout
#include &lt;vector&gt; // vector
#include &lt;algorithm&gt; // for_each
#include &lt;iterator&gt; // istream_iterator
using namespace std;

int main()
{
 std::vector&lt;int&gt; v(10,2);
 std::for_each(v.begin(), v.end(), [](int i)-&gt;void {std::cout &lt;&lt; i &lt;&lt;endl;});
 return 0;
}
</code></pre>

For reading "n" values from cin to vector,

<pre><code> int main()
 {
 std::vector&lt;int&gt; v;

 int elementsToRead;
 cin&gt;&gt;elementsToRead; // Number of elements to copy

 // Reading from istream
 std::istream_iterator&lt;int&gt; ii2(std::cin);
 std::copy_n(ii2, elementsToRead, std::back_inserter(v));

 // printing updated vector
 std::for_each(v.begin(), v.end(), [](int i)-&gt;void {cout &lt;&lt; i &lt;&lt;endl;});

 return 0;
}
</code></pre>

(or) by using Lambda expression

<pre><code>std::for_each(std::istream_iterator&lt;int&gt;(cin),std::istream_iterator&lt;int&gt;(),[&amp;v](int i)-&gt;void { v.push_back(i);});
</code></pre>

To know more about Lambda expression @ <a href="https://stackoverflow.com/questions/7627098/what-is-a-lambda-expression-in-c11">What is a lambda expression in C++11?</a>

blocks|key|879851|text|我知道带迭代器的copy是最好的解决方案，但我只想用for_each来回答。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|879852|你可以这样做：|879853|#include+<vector>
#include+<algorithm>
#include+<locale>

int+main()+{
++using+namespace+std;
++locale::global(locale(""));
++wcout::imbue(locale());

++vector<int>+vec{1000,2000,3000,4000,5000};
++for_each(vec.begin(),+vec.end(),+[](auto+&x){wcout+<<+x+<<+endl;});
++
++return+0;
}|code-block|syntax|javascript|879854|但是，对我来说，它确实比简单的for更具可读性...|879855|#include+<vector>
#include+<locale>

int+main()+{
++using+namespace+std;
++locale::global(locale(""));
++wcout::imbue(locale());

++vector<int>+vec{1000,2000,3000,4000,5000};
++for(auto+&v:+vec)+{
++++wcout+<<+v+<<+endl;
++}
++
++return+0;
}|879856|entityMap^0|8|4|Q|8|0|0|0|F|3|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@$9|T|A|U|B|C]|$9|V|A|W|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|X|8|@]|D|@]|E|$]]|$1|H|3|I|5|J|7|Y|8|@]|D|@]|E|$K|L]]|$1|M|3|N|5|6|7|Z|8|@$9|10|A|11|B|C]]|D|@]|E|$]]|$1|O|3|P|5|J|7|12|8|@]|D|@]|E|$K|L]]|$1|Q|3|-4|5|6|7|13|8|@]|D|@]|E|$]]]|R|$]]

I know the <code>copy</code> with the iterator is the optimal solution, but just to answer with <code>for_each</code>.
You could do:
<pre class="lang-cpp prettyprint-override"><code>#include &lt;vector&gt;
#include &lt;algorithm&gt;
#include &lt;locale&gt;

int main() {
 using namespace std;
 locale::global(locale(&quot;&quot;));
 wcout::imbue(locale());

 vector&lt;int&gt; vec{1000,2000,3000,4000,5000};
 for_each(vec.begin(), vec.end(), [](auto &amp;x){wcout &lt;&lt; x &lt;&lt; endl;});
 
 return 0;
}
</code></pre>
But, for me, it's REALLY much more readable the simple <code>for</code> ...
<pre class="lang-cpp prettyprint-override"><code>#include &lt;vector&gt;
#include &lt;locale&gt;

int main() {
 using namespace std;
 locale::global(locale(&quot;&quot;));
 wcout::imbue(locale());

 vector&lt;int&gt; vec{1000,2000,3000,4000,5000};
 for(auto &amp;v: vec) {
 wcout &lt;&lt; v &lt;&lt; endl;
 }
 
 return 0;
}
</code></pre>

Is there a more straight-forward way to do this?

<code>for_each(v_Numbers.begin(), v_Numbers.end(), bind1st(operator&lt;&lt;, cout));</code>

Without an explicit <code>for</code> loop, if possible.

EDIT:

How to do this for <code>std::cin</code> with a <code>std::vector</code> if possible? (How to read <code>n</code> elements only)?

How do I use for_each to output to cout?

容器

有没有更直接的方法来做到这一点？for_each(v_Numbers.begin(), v_Numbers.end(), bind1st(operator<<, cout));如果可能的话，没有显式的for循环。编辑：如果可能，如何使用std::vector对std::cin执行此操作？(如何只读取n元素)？

问如何使用for_each输出到cout？
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