C++ Institute Exam CPP Topic 2 Question 69 Discussion

Actual exam question for C++ Institute's CPP exam

Question #: 69
Topic #: 2

[All CPP Questions]

What happens when you attempt to compile and run the following code?

#include

using namespace std;

struct Even {

bool operator ()(int a) {

return (a % 2)==0?true:false;

}

};

int main () {

int t[] = {1,2,3,2,3,5,1,2,7,3,2,1,10, 4,4,5};

set s(t,t+15);

int number = count_if(s.begin(), s.end(), Even());

cout<< number<

return 0;

}

Program outputs:

Ecompilation error

Show Suggested Answer

Suggested Answer: C

by Skye at Jul 24, 2023, 07:08 AM

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Blair

1 months ago

I'm just gonna go with E) compilation error. Why? Because that's the only answer that doesn't involve any actual coding, and we all know the real answer is whatever the compiler decides it is.

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Galen

7 days ago

I'm leaning towards C) 7 as the output.

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Carlee

11 days ago

I believe the correct output is B) 3.

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Sanda

14 days ago

I think it will output A) 4.

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Thad

2 months ago

Aha! I think I've got it. The set will only contain unique elements, so the duplicates will be ignored. That means the answer is A) 4. Nailed it!

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Carry

1 months ago

So the count_if function will return the number of even elements, which is 4.

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Fabiola

1 months ago

Yes, you're right. The duplicates will be ignored in the set.

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Aileen

1 months ago

I think the answer is A) 4 because the set will only contain unique elements.

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Kaitlyn

2 months ago

Wait, wait, wait. Didn't we learn that count_if() counts the number of elements for which the predicate is true? So the answer should be B) 3. I hope I'm not missing something obvious here.

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Paz

1 days ago

I think you're right, the answer should be B) 3.

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Herminia

8 days ago

Exactly, the code is counting the number of even numbers in the set.

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Melynda

14 days ago

So, the output should be 3 because the Even struct checks for even numbers.

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Hyun

22 days ago

Yes, count_if() counts the number of elements for which the predicate is true.

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Evangelina

27 days ago

That's right, count_if() counts the number of elements for which the predicate is true. So the answer is indeed B) 3.

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Ty

1 months ago

I think you're right, the answer should be B) 3.

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Evangelina

1 months ago

Yes, you are correct. The answer is B) 3.

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Annice

2 months ago

Ah, I see what's going on here. The set is created with 15 elements, but we're only checking the first 7. So the answer must be D) 8. Easy peasy!

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Rashida

2 months ago

Hmm, this looks like a tricky one. Let's see, we're using a custom 'Even' functor to count the even numbers in a set. I'm guessing the answer is C) 7, since the set contains 7 even numbers.

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