Why debug assertion failure is coming.

[aalam]

class base
{
int a;
base(int x)
{
a=x;
}
~base();
}
class derive:public base
{
derive(int x):base(x){}
virtual display()
{
cou<<"in display method";
}
~derive();
}

void main()
{
derive* d = new derive(10);
base* m = d;
delete(m);
}

if you run the code in debug environment , assertion failure will come.Can anybody tell me why.Its fine that if i make derive class destructor virtual then assertion won't come, but why.

[weaknessforcats]

Submit some code that compiles. All of your member functions are private and there is no cou.