Problem-solving-with-JavaScript/problem-27.js at master · anasmak04/Problem-solving-with-JavaScript · GitHub

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// binary search implementation

const arr = [1, 3, 5, 7, 8, 9];

const binarySearch = (arr, x, start = 0, end = arr.length) => {

// If the item does not exist, return -1

if (end < start) return -1;

// Calculate middle index of the array

let mid = Math.floor((start + end) / 2);

// Is the middle a match?

if (arr[mid] === x) return mid;

// Is the middle less than x

if (arr[mid] < x) return binarySearch(arr, x, mid + 1, end);

// Else the middle is more than x

else return binarySearch(arr, x, start, mid - 1);

};

console.log(binarySearch(arr, 9));

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