unsigned long from string

Projects Programming
8 
unsigned long A = (long) strtol(str.c_str(),NULL,0);

Why not use B but some function call which we can't see?
Why cast the damn thing to a singed int again?
Why not use a real null pointer 'nullptr'?

Serial.println("this is B");
Serial.println(A);

Why print A if you tell it's B?

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