// ------------------------------------------------------------
// A small program demonstrating how to remove every Nth element
// from an array using clear, expressive JavaScript patterns.
// ------------------------------------------------------------
/*
This function returns a new array with every Nth element removed.
It performs a single pass over the input array. JavaScript arrays
use zero‑based indexing, so we check (index + 1) % n !== 0 to keep
elements that are *not* in the Nth position.
The variable "size" captures the array length before the loop,
which avoids repeatedly accessing items.length inside the loop.
*/
function removeEveryNth(items, n) {
if (n <= 0) {
throw new Error("n must be a positive integer");
}
const size = items.length; // capture size once
const result = []; // output array
for (let i = 0; i < size; i++) {
if ((i + 1) % n !== 0) {
result.push(items[i]);
}
}
return result;
}
/*
Keeping the main execution block small and focused makes the program
easy to extend. Here we demonstrate the function with a simple example.
*/
const data = Array.from({ length: 20 }, (_, i) => i + 1); // numbers 1–20
const n = 3; // remove every 3rd element
const cleaned = removeEveryNth(data, n);
console.log("Original:", data.join(" "));
console.log(`After removing every ${n}-th element:`, cleaned.join(" "));
/*
run:
Original: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
After removing every 3-th element: 1 2 4 5 7 8 10 11 13 14 16 17 19 20
*/
