返回反向字符串首个元素的迭代器。
const_reverse_iterator rbegin( ) const;
reverse_iterator rbegin( );
返回值
返回一个随机访问迭代器处于已撤消的字符串中的第一个元素,该解决什么是相应的 unreversed 字符串的最后一个元素。
备注
正值 开始 用于字符串,rbegin 使用的反转字符串。
如果返回值 rbegin 为 const_reverse_iterator,不能修改字符串对象。 如果返回值 rbegin 赋给 reverse_iterator,可修改字符串对象。
rbegin 可用来在字符串初始化向后迭代。
示例
// basic_string_rbegin.cpp
// compile with: /EHsc
#include <string>
#include <iostream>
int main( )
{
using namespace std;
string str1 ( "Able was I ere I saw Elba" ), str2;
basic_string <char>::reverse_iterator str_rIter, str1_rIter, str2_rIter;
basic_string <char>::const_reverse_iterator str1_rcIter;
str1_rIter = str1.rbegin ( );
// str1_rIter--;
cout << "The first character-letter of the reversed string str1 is: "
<< *str1_rIter << endl;
cout << "The full reversed string str1 is:\n ";
for ( str_rIter = str1.rbegin( ); str_rIter != str1.rend( ); str_rIter++ )
cout << *str_rIter;
cout << endl;
// The dereferenced iterator can be used to modify a character
*str1_rIter = 'A';
cout << "The first character-letter of the modified str1 is now: "
<< *str1_rIter << endl;
cout << "The full modified reversed string str1 is now:\n ";
for ( str_rIter = str1.rbegin( ); str_rIter != str1.rend( ); str_rIter++ )
cout << *str_rIter;
cout << endl;
// The following line would be an error because iterator is const
// *str1_rcIter = 'A';
// For an empty string, begin is equivalent to end
if ( str2.rbegin( ) == str2.rend ( ) )
cout << "The string str2 is empty." << endl;
else
cout << "The stringstr2 is not empty." << endl;
}
要求
标头:< 字符串>
命名空间: std