Halloween Candy cpp

Question

Why the output is 0 (to any input)?

#include <iostream>
using namespace std;

int main() {
int houses;
cin>>houses;

//your code goes here
int res;
res=2/houses*100;
cout<<res<<endl;
return 0;
}

Answer 1

Because if you use houses of type int, the number will be rounded. For example, let s say your input is 5.
2/5 will give you 0 because the number will be rounded. Try the data types "double" or "float" for the input and res.

Answer 2

🍇 Alex Tușinean 💜can you please explain why is it correct:

#include <iostream>
#include <cmath>
using namespace std;

int main() {
float houses;
cin>>houses;

//your code goes here
float res;
res=2/houses*100;
cout<<ceil(res)<<endl;
return 0;
}

while the same code with int houses is not? Am I not supposed to use integers as a denominator when the result has a float/double type or what?