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binarySearch.js

const binarySearch = (array, item) => {
  let low = 0;
  let high = array.length - 1;

  let iter = 1;

  while(low <= high) {
    let middle = parseInt((high + low) / 2);
    let value = array[middle];

    console.log(`${iter}. value: ${value}`)

    if (value === item) {
      return value;
    }

    if (value > item) {
      high = middle - 1;
    } else {
      low = middle + 1;
    }

    iter += 1;
  }

  return null;
};

const array = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
const item = 1;

binarySearch(array, item);
// 1. value: 5
// 2. value: 2
// 3. value: 1