#2059 - Minimum Operations to Convert Number

Problem 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.

Solution

/**
 * @param {number[]} nums
 * @param {number} start
 * @param {number} goal
 * @return {number}
 */
var minimumOperations = function(nums, start, goal) {
  const queue = [[start, 0]];
  const visited = new Set([start]);

  while (queue.length) {
    const [current, steps] = queue.shift();

    for (const num of nums) {
      const candidates = [
        current + num,
        current - num,
        current ^ num
      ];

      for (const next of candidates) {
        if (next === goal) {
          return steps + 1;
        }
        if (next >= 0 && next <= 1000 && !visited.has(next)) {
          visited.add(next);
          queue.push([next, steps + 1]);
        }
      }
    }
  }

  return -1;
};