MinimumDistanceToTargetElement.php

<?php

namespace App;

/**
 * Minimum Distance to the Target Element
 *
 * Given an integer array nums (0-indexed) and two integers target and start, find an index i such that
 * nums[i] == target and abs(i - start) is minimized. Note that abs(x) is the absolute value of x. Return abs(i - start)
 * It is guaranteed that target exists in nums.
 *
 * Example 1:
 * Input: nums = [1,2,3,4,5], target = 5, start = 3
 * Output: 1
 * Explanation: nums[4] = 5 is the only value equal to target, so the answer is abs(4 - 3) = 1.
 *
 * Example 2:
 * Input: nums = [1], target = 1, start = 0
 * Output: 0
 * Explanation: nums[0] = 1 is the only value equal to target, so the answer is abs(0 - 0) = 0.
 *
 * Example 3:
 * Input: nums = [1,1,1,1,1,1,1,1,1,1], target = 1, start = 0
 * Output: 0
 * Explanation: Every value of nums is 1, but nums[0] minimizes abs(i - start), which is abs(0 - 0) = 0.
 *
 * https://leetcode.com/problems/minimum-distance-to-the-target-element
 */
class MinimumDistanceToTargetElement
{
    /**
     * @param int[] $nums
     * @param int $target
     * @param int $start
     * @return int
     */
    public function getMinDistance(array $nums, int $target, int $start): int
    {
        $minDistance = PHP_INT_MAX;
        /** @var int $index */
        foreach ($nums as $index => $num) {
            if ($num === $target) {
                $minDistance = min($minDistance, abs($index - $start));
            }
        }
        return $minDistance;
    }
}