为什么istringstream iss.get(chr);最后一个字符总是多输出一个？

[chenhaifeng88888]

为什么istringstream iss.get(chr);最后一个字符总是多输出一个？

#include <stdio.h>
#include <string>
#include <iostream>
#include <sstream>
#include <fstream>

using namespace std;

int main()
{
	istringstream iss;
	char chr;
	iss.str("f");
	while (1)
	{
		iss.get(chr);
		printf("%c\n", chr);
		cout << iss.eof() << endl;
		if (iss.eof())
			break;
	}
}


f
0
f
1

#include <stdio.h>
#include <string>
#include <iostream>
#include <sstream>
#include <fstream>

using namespace std;

int main()
{
	istringstream iss;
	char chr;
	iss.str("fxs");
	while (1)
	{
		iss.get(chr);
		printf("%c\n", chr);
		cout << iss.eof() << endl;
		if (iss.eof())
			break;
	}
}

f
0
x
0
s
0
s
1

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