[Dev-C++] floating point numbers

[P.Lane <kc...@gm...>]

Hello, I am new to programming and to c++ and Dev-CPP. I have been
experimenting with numbers and can't figure this one out. Here is the
code the I am using:

#include<iostream>
using namespace std;
int main ()
{
    int a;
    float b;
    double c;
    long double d;
    cout << " Enter a number:  ";
    cin >> d;
    c=3Dd;
    b=3Dd;
    a=3Dd;
    cout << d << endl << c << endl << b << endl << a << endl;
    return 0;
}
Here is the result with the number 123456789.123456789:
1.23457e+008
1.23457e+008
1.23457e+008
123456789
Now from what I have read, a long double should be good up to 19
digits, a long up to 15, and a float up to 7. Why does the long double
return 1.23457e+008, instead of the entered value of
123456789.123456789, which is only 18 digits long?

--=20
Paul Lane
KC9EYE
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--
"Life after all, is a fatal disease, and the mortality rate=20
for humans, at the end of the day is 100%."
K.C. Cole
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