#2059

Minimum Operations to Convert Number

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Description

You are given a 0-indexed integer array nums containing distinct numbers, an integer start, and an integer goal. There is an integer x that is initially set to start, and you want to perform operations on x such that it is converted to goal. You can perform the following operation repeatedly on the number x:

If 0 <= x <= 1000, then for any index i in the array (0 <= i < nums.length), you can set x to any of the following:

- x + nums[i]

- x - nums[i]

- x ^ nums[i] (bitwise-XOR)

Note that you can use each nums[i] any number of times in any order. Operations that set x to be out of the range 0 <= x <= 1000 are valid, but no more operations can be done afterward.

Return the minimum number of operations needed to convert x = start into goal, and -1 if it is not possible.

Example 1:

Input: nums = [2,4,12], start = 2, goal = 12

Output: 2

Explanation: We can go from 2 → 14 → 12 with the following 2 operations.

- 2 + 12 = 14

- 14 - 2 = 12

Example 2:

Input: nums = [3,5,7], start = 0, goal = -4

Output: 2

Explanation: We can go from 0 → 3 → -4 with the following 2 operations.

- 0 + 3 = 3

- 3 - 7 = -4

Note that the last operation sets x out of the range 0 <= x <= 1000, which is valid.

Example 3:

Input: nums = [2,8,16], start = 0, goal = 1

Output: -1

Explanation: There is no way to convert 0 into 1.

Solution