c++ - 使用用户输入 C++ 创建 n 个不同的 vector

Question

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Answer 1

有几点需要注意。

std::vector有一个 push_back()接受你的 vector 被定义为的方法。所以如果你做 vector<int>然后 push_back(would_take_an_int_here) .

您可以在此处阅读有关 vector 及其属性的信息:

http://en.cppreference.com/w/cpp/container/vector

就您正在寻找的内容而言，以上面的示例为例，让我们对其进行扩展。

所以你想要一个 vector 的 vector ？这意味着 push_back(needs_to_take_a_vector)

让我们从技术代码片段开始:

//First we define the vector

vector<int> x; //this is a vector of integers

vector<vector<int>> x; //this is a vector of integer vectors

//Now we want to let the user enter the amount of vectors needed.   
//We would probably want a for-loop, because it is a count based loop and we    
//know exactly how much the user wants to enter.

for(int i = 0; i < user_input; i++) {
    vector<int> my_vec;
    //This allows the vector<int> to be populated
    //before being pushed back to x, not necessary though.
    my_vec.push_back(i);
    x.push_back(my_vec);
}

在循环之后我会尝试做一件巧妙的事情，只是为了看看你是否确实在你的 vector 中实现了你想要的，是这样的:

//notice there is a .size() function for vectors to see how many elements are 
//inside the vector.
std::cout << "My user asked for " << user_input << " vectors, and my vectors size is " << my_vec.size() << " elements big" << endl;

我希望其中的一些内容能够解释某些部分，并超出您想要的范围，以便您能够理解!