pi program

[mzfhhhh via Digitalmars-d-learn]

> If we worry about the string form and instead try:
>
> double reduce_string_loop() {
>   return reduce!"1.0 / (a * a)"(iota(1, 100));
> }
>
> double reduce_function_loop() {
>   return reduce!((n) => 1.0 / (n * n))(iota(1, 100));
> }
>

it should be write :
double reduce_loop() {
   //return iota(1, 100).map!"1.0 / (a * a)".sum;
   return iota(1, 100).reduce!"a + 1.0 / (b * b)";
}