#1909 - Remove One Element to Make the Array Strictly Increasing

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Problem Description

Given a 0-indexed integer array nums, return true if it can be made strictly increasing after removing exactly one element, or false otherwise. If the array is already strictly increasing, return true.

The array nums is strictly increasing if nums[i - 1] < nums[i] for each index (1 <= i < nums.length).

Solution

/**
 * @param {number[]} nums
 * @return {boolean}
 */
var canBeIncreasing = function(nums) {
  for (let i = 0; i < nums.length; i++) {
    if (isStrictlyIncreasing(nums, i)) return true;
  }

  return false;

  function isStrictlyIncreasing(arr, skipIndex) {
    for (let i = 1; i < arr.length; i++) {
      if (i === skipIndex) continue;
      const prev = i - 1 === skipIndex ? i - 2 : i - 1;
      if (prev >= 0 && arr[i] <= arr[prev]) return false;
    }
    return true;
  }
};