c++ - Passing custom class object as a value into STL map -

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i want pass object of custom class value stl map. how do that..?

here code:

class demo {  int a, b,c,d,e;  }  // here how declare map:  map<int, demo*> my_map;

this how, using function:

demo *ptr = null; ptr = new demo;

here how inserting map

my_map.insert(make_pair(int, ptr);  // delete current instance  delete ptr;

is correct way..?

actually, no. if want store demo objects in map, should use map<int, demo>. leave resource management std::map. also, using delete ptr destroy created object, , my_map[index] invalid pointer.

just use my_map.insert(make_pair(myindex, mydemoobject));.

also note using my_map[myindex] create object given index if doesn't exist, can following:

std::map<int, demo> my_map; my_map[1].a = 42; my_map[2].b = 1337; my_map[3].c = 314159; my_map[4].d = 23;

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