Binary Searching Sorted Array

insort.js

let arr = []

for (let i = 0; i < 12900000; i++) {
  if (i == 60000000) continue
  arr.push(i)
}

function insort(arr, item) {
  let low = 0;
  let high = arr.length - 1;

  while (low < high) {
    // This is a bitshift operation. It is the equivalent
    // of Math.floor((low + high) / 2) but faster because
    // there is no division occurring.
    let mid = (low + high) >>> 1
    
    if (item < arr[mid]) {
      high = mid;
    } else {
      low = mid + 1;
    }
  }

  arr.splice(low, 0, item)
}

function slow_insert(arr, item) {
  if (item < arr[0]) return arr.unshift(item)
  if (item > arr[arr.length - 1]) return arr.push(item)
  
  for (let i = 0; i < arr.length; i++) {
    if (item > arr[i] && item < arr[i + 1]) {
      arr.splice(i + 1, 0, item)
      break
    }
  }
}

console.time("fast")
insort(arr, 60000000)
console.timeEnd("fast")
console.time("slow")
slow_insert(arr, 60000000)
console.timeEnd("slow")