a simple question

[manojg]

Hi,

What is the difference between

double a = 4.5;

and

double a(4.5);

Both gives the same output with

cout << a << endl;

Thanks.

[Paul McKenzie]

Hi,

What is the difference between

double a = 4.5;

and

double a(4.5);

Both gives the same output with

cout << a << endl;

Thanks.

There is no difference. In C++, even though "a" is a simple double, for consistency it is advantageous for the syntax to initialize this variable to be similar to object initialization.

#include <string>

int main()
{
   std::string s1("abc123");
   std::string s2 = "abc123";
}

Note the similarities between the code above using the std::string class, and your code using the double.

Regards,

Paul McKenzie

[manojg]

Thanks.

[laserlight]

Note that there may be a difference if the type is a class type rather than double, i.e., the former would not be allowed if the corresponding constructor was declared as explicit.