Question

help with c++

Answer 1

so z is a float variable, it says that x = y * z is bad programming style but i don't know why.

Answer 2

from what i understand i think i have to write it as x = y + (int)z

Answer 3

Like they were talking about, it has to do with rounding errors.

Answer 4

Know how in decimal 1/3 is an ininite sequence of .3? Well, there are things like that in binary too. So these add up pretty qick as mistakes in the math.

Answer 5

the entire code section is
int x, y = 4;
float z = 2.7
x = y * z;

Answer 6

Well there you are going to truncate the float because you are multiplying a float times an int as assigning to a float. That will cause loss.

Answer 7

so i should do (float)x = (float)y + z; ?

Answer 8

Well, you would still have ussues. It is simply best to never mix floats and ints. Floats are always estimates and ints are always exact.

Answer 9

well what do think is the best way to write it?

Answer 10

I need help with it too. I learned Java script.

Answer 11

If you need to use floats, have them all be floats.

Answer 12

well im only supposed to change this section x = y * z

Answer 13

Then you would have to cast the float to an int, which will cause loss no matter what.

Answer 14

okay thx

Answer 15

```
#include <iostream>

int main() {
int x1, y1=4;
float z1=2.7;
x1 = y1 * z1;
float x2, y2=4;
float z2=2.7;
x1 = y1 * z1;
x2 = y2 * z2;
std::cout << "As ints\n";
std::cout << x1 << std::endl;
std::cout << "\nAs floats\n";
std::cout << x2 << std::endl;
getchar();
return 0;
}
```
As ints
10

As floats
10.8

Answer 16

instead of std::cout can we use using namespace std; before "int main()"

Answer 17

Yes, you can set the namespace. Over the long term, you will get away from loading an entire namespace when you only need a few packages from it.