Assign object into unordered_map array?

[jaden5165]

    typedef tr1::unordered_map <string, pin *> pin_cmp;
    pin_cmp _pin_cmp;
    _Pins[_num_pins] = new pin (pin_id, _num_pins, s, n, d);
    _pin_cmp[_Pins[_num_pins]->get_name ()] = _Pins[_num_pins]; //performance profiling 

Could you teach me what actually the code doing?

_pin_cmp[_Pins[_num_pins]->get_name ()] = _Pins[_num_pins]; //performance profiling

I am not familiar with unordered_map which still can use with array[].I am confuse unordered_map just need key and value why will have array[]?

[TheIdeasMan]

Do these help?

http://www.cplusplus.com/reference/unordered_map/unordered_map/
http://www.cplusplus.com/reference/unordered_map/unordered_map/operator%5B%5D/