std::make_pair
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| 在头文件 <utility> 中定义
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| （至 C++11） （C++11 起） |
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创建一个
std::pair对象，推导出目标类型的参数类型.原文：
Creates a
std::pair object, deducing the target type from the types of arguments.推导的类型是std::decay<T1>::type和std::decay<T2>::type（通常的类型转换施加到通过值的函数的参数），除非对于某些类型std::decay，在这种情况下，推导出的类型是std::reference_wrapper<X>
XX&结果应用。 （C++11 起）原文：
The deduced types are std::decay<T1>::type and std::decay<T2>::type (the usual type transformations applied to arguments of functions passed by value) unless application of std::decay results in std::reference_wrapper<X> for some type
X, in which case the deduced type is is X&. （C++11 起）[编辑] 参数
| t, u | - | 值来构建对
原文： the values to construct the pair from |
[编辑] 返回值
[编辑] 示例
#include <iostream> #include <utility> #include <functional> int main() { int n = 1; int a[5] = {1,2,3,4,5}; // build a pair from two ints auto p1 = std::make_pair(n, a[1]); std::cout << "The value of p1 is " << "(" << p1.first << ", " << p1.second << ")\n"; // build a pair from a reference to int and an array (decayed to pointer) auto p2 = std::make_pair(std::ref(n), a); n = 7; std::cout << "The value of p2 is " << "(" << p2.first << ", " << *(p2.second+1) << ")\n"; }
输出：
The value of p1 is (1, 2) The value of p2 is (7, 2)
