[your code here]

[Paul Backus]

On Wednesday, 28 April 2021 at 07:56:50 UTC, drug wrote:
> ```D
>         .map!((a)=>(gcd(a[0], a[1]) == 1) ? 1 : 0)
>         .sum(0);
> ```

Alternatively:

```d
.filter!(pair => gcd(pair[0], pair[1]) == 1)
.count;
```