一个简单的线性映射：

#include
      
       #include
       
        using namespace std;template
        
         class LinearMap{public:    LinearMap(int size = 101) :arr(size)    {        current_size = 0;    }    void Put(const Key&k, const Value&v)    {        arr[current_size] = DataEntry(k, v);        ++current_size;    }    Value Get(const Key&k)    {        for (int i = 0; i < current_size; ++i)        {            if (arr[i].key == k)                return arr[i].value;        }        return Value();    }private:    struct DataEntry{        Key key;        Value value;        DataEntry(const Key&k = Key(), const Value&v = Value()) :key(k), value(v){};    };    vector
         
           arr;    int current_size;};int main(){    LinearMap
          
            lm;    lm.Put("tom", 99);    lm.Put("Jack", 88);    lm.Put("ly", 77);    cout << lm.Get("Jack") << endl;    return 0;}