const arr = Array.from({ length: 200000 }, (v, ind) => ind)
let sum = 0
for (let i = 0; i < arr.length; i++) {
sum += arr[i]
if (i === 1000) arr.pop()
}
for (let i = 0, l = arr.length; i < l; i++) {
sum += arr[i]
if (i === 1000) { arr.pop(), l-- }
}