34 lines
939 B
C++
34 lines
939 B
C++
|
#include <bits/stdc++.h>
|
||
|
|
using namespace std;
|
||
|
|
|
||
|
|
template <typename T> class Number {
|
||
|
|
template <typename U> friend Number<U> &operator++(Number<U> &);
|
||
|
|
|
||
|
|
public:
|
||
|
|
using iterator_category = forward_iterator_tag;
|
||
|
|
using value_type = T;
|
||
|
|
using difference_type = ptrdiff_t;
|
||
|
|
using pointer = const T *;
|
||
|
|
using reference = const T &;
|
||
|
|
Number(T a) : dat(a) {}
|
||
|
|
bool operator==(const Number<T> &o) const { return dat == *o; }
|
||
|
|
bool operator!=(const Number<T> &o) const { return dat != *o; }
|
||
|
|
const T &operator*() const { return dat; }
|
||
|
|
Number<T> operator+(ptrdiff_t dt) { return Number<T>(dat + dt); }
|
||
|
|
|
||
|
|
private:
|
||
|
|
T dat;
|
||
|
|
void _plusplus() { ++dat; }
|
||
|
|
};
|
||
|
|
|
||
|
|
template <typename T> Number<T> &operator++(Number<T> &it) {
|
||
|
|
it._plusplus();
|
||
|
|
return it;
|
||
|
|
}
|
||
|
|
|
||
|
|
int main() {
|
||
|
|
auto cmp = [](int a, int x) { return a <= x; };
|
||
|
|
cout << *lower_bound(Number(1), Number(5), 3, cmp); // cout << 3 + 1;
|
||
|
|
return 0;
|
||
|
|
}
|