33-Search-in-Rotated-Sorted-Array.js

/**
 * @param {number[]} nums
 * @param {number} target
 * Time O(log(N)) | Space O(1)
 * @return {number}
 */
var search = (nums, target) => {
    let [left, right] = [0, nums.length - 1];

    while (left <= right) {
        const mid = (left + right) >> 1;
        const guess = nums[mid];
        const [leftNum, rightNum] = [nums[left], nums[right]];

        const isTarget = guess === target;
        if (isTarget) return mid;

        const isAscending = leftNum <= guess;
        if (isAscending) {
            const isInRange = leftNum <= target;
            const isLess = target < guess;

            const isTargetGreater = !(isInRange && isLess);
            if (isTargetGreater) left = mid + 1;

            const isTargetLess = isInRange && isLess;
            if (isTargetLess) right = mid - 1;
        }

        const isDescending = guess < leftNum;
        if (isDescending) {
            const isGreater = guess < target;
            const isInRange = target <= rightNum;

            const isTargetGreater = isGreater && isInRange;
            if (isTargetGreater) left = mid + 1;

            const isTargetLess = !(isGreater && isInRange);
            if (isTargetLess) right = mid - 1;
        }
    }

    return -1;
};