34.FindRangeInSortedArray.js

/**
 * 
✔ Accepted
  ✔ 88/88 cases passed (84 ms)
  ✔ Your runtime beats 84.08 % of javascript submissions
  ✔ Your memory usage beats 35.88 % of javascript submissions (35.1 MB)
 */

var searchRange$1 = function (nums, target) {
    var mid = Math.floor(nums.length / 2);
    if (nums[0] > target || nums[nums.length - 1] < target) return [-1, -1];

    // 判断往那边
    var count = 0;
    var l = mid;
    var r = mid;
    if (target > nums[mid]) {
        count = 1;
    } else if (target < nums[mid]) {
        count = -1;
    }

    while (nums[mid] != target) {
        mid += count;
        l = mid;
        r = mid;
        if (mid > nums.length - 1 || mid < 0) {
            return [-1, -1];
        }
    }
    while (nums[mid] == nums[mid + 1]) {
        mid++;
        r = mid;
    }
    while (nums[mid - 1] == nums[mid]) {
        mid--;
        l = mid;
    }
    return [l, r];
};

var searchRange$2 = function (nums, target) {
    const res1 = nums.slice(0).reduce((acc, cur, index, arr) => {
        if (cur === target) {
            acc.push(index);
            arr.splice(1);
            return acc;
        }
        return acc;
    }, []);
    const res2 = nums.slice(0).reduceRight((acc, cur, index, arr) => {
        if (cur === target) {
            acc.push(index);
            arr = [];
            return acc;
        }
        return acc;
    }, []);
    if (res1.length > 0) {
        return res1.concat(res2[0]);
    } else {
        return [-1, -1];
    }
};