如何将 vector::push_back()` 与结构一起使用?

2021-12-21 00:00:00 vector c++

如何将 push_back struct 转化为向量?

How can I push_back a struct into a vector?

struct point {
    int x;
    int y;
};

std::vector<point> a;

a.push_back( ??? );

推荐答案

point mypoint = {0, 1};
a.push_back(mypoint);

或者如果你被允许,给 point 一个构造函数,这样你就可以使用一个临时的:

Or if you're allowed, give point a constructor, so that you can use a temporary:

a.push_back(point(0,1));

如果你在一个用struct声明的类中放置一个构造函数,有些人会反对,这使它成为非POD,也许你无法控制point的定义.因此,您可能无法使用此选项.但是,您可以编写一个提供相同便利的函数:

Some people will object if you put a constructor in a class declared with struct, and it makes it non-POD, and maybe you aren't in control of the definition of point. So this option might not be available to you. However, you can write a function which provides the same convenience:

point make_point(int x, int y) {
    point mypoint = {x, y};
    return mypoint;
}

a.push_back(make_point(0, 1));

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