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Pair

The library includes templates for heterogeneous pairs of values.

T1 first	Instance Variable of pair
T2 second	Instance Variable of pair

pair ()	Constructor on pair
pair (const T1& x, const T2& y)	Constructor on pair
==	Operator on pair
<	Operator on pair

template 
struct pair {
    T1 first;
    T2 second;
    pair() {}
    pair(const T1& x, const T2& y) : first(x), second(y) {}
};

template 
inline bool operator==(const pair& x, const pair& y) 
{
    return x.first == y.first && x.second == y.second;
}

template 
inline bool operator<(const pair& x, const pair& y) 
{
    return x.first < y.first || (!(y.first < x.first) && x.second < y.second);
}

pair<T1, T2> make_pair

Function

The library provides a matching template function make_pair to simplify their construction. Instead of saying, for example,

return pair(5, 3.1415926); // explicit types

return make_pair(5, 3.1415926); // types are deduced
template 




inline pair make_pair(const T1& x, const T2& y)
{
    return pair(x, y);
}