如何重置迭代器，再次使用该迭代器访问数据

[dianyancao]

如何再次从cin中读取字符？

#include <iostream>
#include <iterator>
#include <vector>
#include <numeric>

using namespace std;

int main(int argc,char* argv[])
{
	vector<int> numbers;
	istream_iterator<int> numbersInput(cin),numbersEnd;

	while (numbersInput!=numbersEnd)
	{
		numbers.push_back(*numbersInput++);
	}
	cout<<accumulate(numbers.begin(),numbers.end(),0)<<endl;
	
	cin.ignore(1024,'\t');
	cin.clear();
	numbersInput=istream_iterator<int>(cin);    //如何重置该迭代器，再次从cin中读取字符？
	cout<<accumulate(numbersInput,numbersEnd,0)<<endl;

	system("PAUSE");
	return EXIT_SUCCESS;
}

[dianyancao]

http://www.cplusplus.com/reference/istream/istream/sync/

[飞天御剑流]

引用 楼主 dianyancao 的回复:

如何再次从cin中读取字符？

#include <iostream>
#include <iterator>
#include <vector>
#include <numeric>

using namespace std;

int main(int argc,char* argv[])
{
	vector<int> numbers;
	istream_iterator<int> numbersInput(cin),numbersEnd;

	while (numbersInput!=numbersEnd)
	{
		numbers.push_back(*numbersInput++);
	}
	cout<<accumulate(numbers.begin(),numbers.end(),0)<<endl;
	
	cin.ignore(1024,'\t');
	cin.clear();
	numbersInput=istream_iterator<int>(cin);    //如何重置该迭代器，再次从cin中读取字符？
	cout<<accumulate(numbersInput,numbersEnd,0)<<endl;

	system("PAUSE");
	return EXIT_SUCCESS;
}

不用搞这么多代码，两三行完事：

std::vector< int > example;
    while( 1 )
    {
        copy( std::istream_iterator< int >( std::cin ), std::istream_iterator< int >(), back_inserter( example ) );
        copy( example.begin(), example.end(), std::ostream_iterator< int >( std::cout, " ") );
    }

[有新工作否]

#include <iostream>
#include <iterator>
#include <vector>
#include <numeric>
 
using namespace std;
 
int main(int argc,char* argv[])
{
    vector<int> numbers;
    istream_iterator<int> numbersInput(cin),numbersEnd;
 
    while (numbersInput!=numbersEnd)
    {
        numbers.push_back(*numbersInput++);
    }
    cout<<accumulate(numbers.begin(),numbers.end(),0)<<endl;
     
    //cin.ignore(1024,'\t');
    cin.clear();
	cin.sync();
    
	numbersInput = cin;

	while (numbersInput!=numbersEnd)
    {
        numbers.push_back(*numbersInput++);
    }
    cout<<accumulate(numbers.begin(),numbers.end(),0)<<endl;
 
    system("PAUSE");
    return EXIT_SUCCESS;
}

刷新cin用cin.sync();

[十八道胡同]

参考http://www.cplusplus.com/reference/istream/istream/

[dianyancao]

不行哦，输入字母，成死循环了，要再次输入呢

[飞天御剑流]

自行添加cin.clear()和cin.sync()就行了，这些事情应该自己会做，不需要别人提了。