Range-based for loop in c++ 11

执行在一个区域上的遍历。

Range-based for loops 的基本语法

vector<int> vec;
vec.push_back( 10 );
vec.push_back( 20 );
 
for (int i : vec )
{
    cout << i;
}

也可以使用 auto 关键字

map<string, string> address_book;
for ( auto address_entry : address_book )
{
            cout  << address_entry.first << " < " << address_entry.second << ">" << endl;
}

修改Vector的内容

vector<int> vec;
vec.push_back( 1 );
vec.push_back( 2 );
 
for (int& i : vec )
{
    i++; // increments the value in the vector
}
for (int i : vec )
{
    // show that the values are updated
    cout << i << endl;
}

What does it mean to have a range?

Strings,arrays, 和所有的STL容器。