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a c++ question

a c++ question# Programming - 葵花宝典

p*g2005-10-26 07:10

1 楼

Since std::set::iterator only support ++ and --, i write a piece of code to do
the + (and -) functionality.
the code is below:
set::const_iterator& operator+(set::const_iterator& it, const int& n
)
{
for (int i=0; ireturn it;
}
it works fine. But only for set. I want to write a generic function, the
code is
template
set::const_iterator& operator+(set::const_iterator& it, const int& n)
{
for (int i=0; ireturn it;
}
Even more gene

t*q2005-10-26 07:10

2 楼

why not use the built-in "advance" function?

do
n
the

【在 p******g 的大作中提到】

: Since std::set::iterator only support ++ and --, i write a piece of code to do
: the + (and -) functionality.
: the code is below:
: set::const_iterator& operator+(set::const_iterator& it, const int& n
: )
: {
: for (int i=0; i: return it;
: }
: it works fine. But only for set. I want to write a generic function, the

p*g2005-10-26 07:10

3 楼

yeah right, surely you can use it but what if there is no advance?
hehe just for the sake of pedagogy, how to solve the problem?
I come up with an ugly solution
template
struct MyIter : T::iterator {
MyIter(const T& a) : T::iterator(a.begin()) {};
MyIter& operator+(const int& n);
};
template
MyIter& MyIter::operator+(const int& n)
{
for (int i=0; ireturn *this;
}
Any better idea? it seems I can't use "T::iterator &" why?

【在 t*q 的大作中提到】

: why not use the built-in "advance" function?
:
: do
: n
: the