binary-search-recursive.ts

function BinarySearchRecursive(array: number[], key, startIndex: number, lastIndex: number): number {
    const mid = Math.floor((startIndex + lastIndex) / 2);
    if (!(startIndex <= lastIndex)) {
        return -1;
    } else if (key === array[mid]) {
        return mid;
    } else if (key < array[mid]) {
        BinarySearchRecursive(array, key, startIndex, mid - 1);
    } else {
        BinarySearchRecursive(array, key, mid + 1, lastIndex);
    }
}