在c ++中将对插入到map中 [英] Insert pair into map in c++

问题描述

我有以下地图结构：

std::map<std::pair<int, char>, int> transitions;

表示非确定性自动机的转换，每个自动机分为2个整数和一个字符I，J和C，代表转换状态，即转换状态从状态i到状态J，并带有字符C.

That represent the transition of the nondeterministic automaton, each with 2 integers and a character, I, J and C, representing the states where the transition, ie, the transition goes from state i to state J with the character C.

0 0 a
0 1 a
1 1 b
1 2 c
1 3 c
3 4 d
4 4 d
4 5 d

我想插入它。我如何做？

I wish to insert into it. How I can do?

我想到了以下几点：

typedef map<pair<int, char>, int> transitions;
    for (j=0; j<numberTransitions;j++)
    {

        cin>> stateOrigin>>stateDestination>>transitionCharacter;
        transitions.insert(transitions::value_type(std::make_pair(stateOrigin,transitionCharacter), stateDestination ));

    }

我不认为是这样做的方式，我是新手使用地图库。

I do not think that is the way to do it, I am newbie using the map library.

推荐答案

我唯一看到错误的是你需要一个对象：

The only thing I see wrong is you need an object:

    transitions.insert(transitions::value_type(std::make_pair(stateOrigin,transitionCharacter), stateDestination ));
    ^^^^^^^^^^^   is a type


    /// Should be 
    transitions   trans;

    // Then later in the loop.
    trans.insert(transitions::value_type(std::make_pair(stateOrigin,transitionCharacter), stateDestination ));

您甚至可以再进一步使用key_type而不是使用：

You could even take it a step further and use key_type rather than make pair:

trans.insert(transitions::value_type(transitions::key_type(stateOrigin,transitionCharacter), stateDestination ));

// or
for(/*STUFF*/)
{
    typedef transitions::value_type  value_type;
    typedef transitions::key_type    key_type;
    trans.insert(value_type(key_type(stateOrigin,transitionCharacter), stateDestination ));
}

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