Quiz: C++ Interview Questions

5 questionsNo time limitPass: 60%+10 XP on first pass

The C++ questions asked in campus interviews and written tests: C vs C++, references, virtual functions, constructors, the STL, memory — plus tricky output programs, each compiled and explained.

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Question 1

What is printed?

#include <iostream>
using namespace std;
struct P { P() { cout << "P"; } ~P() { cout << "p"; } };
struct C : P { C() { cout << "C"; } ~C() { cout << "c"; } };
int main() { C x; return 0; }

CPpcPCcpPCpcCPcp

Question 2
Which is the only default difference between struct and class?
structs can't have functionsDefault member access: public for struct, private for classclasses can't be inherited fromstructs can't have constructors
Question 3
What problem does a shallow copy of a class with a raw pointer cause?
Faster codeTwo objects share one buffer, leading to double free or unexpected changesCompile errors onlyNothing

Question 4

What does this print?

#include <iostream>
using namespace std;
int main() {
    int x = 10;
    int &y = x;
    y++;
    x *= 2;
    cout << y;
    return 0;
}

10112220

Question 5
What does new do that malloc doesn't?
Allocates on the stackCalls the constructor and returns a typed pointerFrees memory automaticallyNothing — they are identical