Here's a sample code snippet that will initiate a loop in JavaScript using the `urls` array:

```
for (let i = 0; i < urls.length; i++) {
    // code to be executed for each element of the array
    console.log(urls[i]);
}
```

In this example, the `for` loop iterates over the `urls` array using the counter variable `i` and then logs each element to the console using `console.log()`. You can replace the `console.log()` call with any code that needs to be executed for each element of the array.
urls = ["https://example.com/1", "https://example.com/2", "https://example.com/3"]
Dato un set di istruzioni, genera uno snippet di codice JavaScript che avvierà un ciclo.