3741. Minimum Distance Between Three Equal Elements II

/**
 * Problem: LeetCode 3741 - Minimum Distance Between Three Equal Elements II
 * Difficulty: Medium
 * Language: Java
 * Author: CodeByTushu
 */
import java.util.*;

class Solution {
    public int minimumDistance(int[] nums) {
        int n = nums.length;
        int[] prev1 = new int[n + 1];
        int[] prev2 = new int[n + 1];
        Arrays.fill(prev1, -1);
        Arrays.fill(prev2, -1);

        int minDistance = Integer.MAX_VALUE;

        for (int i = 0; i < n; i++) {
            int val = nums[i];
            if (prev2[val] != -1) {
                minDistance = Math.min(minDistance, 2 * (i - prev2[val]));
            }
            prev2[val] = prev1[val];
            prev1[val] = i;
        }

        return minDistance == Integer.MAX_VALUE ? -1 : minDistance;
    }
}

"""
Problem: LeetCode 3741 - Minimum Distance Between Three Equal Elements II
Difficulty: Medium
Language: Python
Author: CodeByTushu
"""
class Solution:
    def minimumDistance(self, nums: list[int]) -> int:
        n = len(nums)
        prev1 = [-1] * (n + 1)
        prev2 = [-1] * (n + 1)
        min_dist = float('inf')

        for i, val in enumerate(nums):
            if prev2[val] != -1:
                min_dist = min(min_dist, 2 * (i - prev2[val]))
            prev2[val] = prev1[val]
            prev1[val] = i

        return min_dist if min_dist != float('inf') else -1

/**
 * Problem: LeetCode 3741 - Minimum Distance Between Three Equal Elements II
 * Difficulty: Medium
 * Language: C++
 * Author: CodeByTushu
 */
#include <vector>
#include <algorithm>
#include <climits>

using namespace std;

class Solution {
public:
    int minimumDistance(vector<int>& nums) {
        int n = nums.size();
        vector<int> prev1(n + 1, -1);
        vector<int> prev2(n + 1, -1);
        int minDistance = INT_MAX;

        for (int i = 0; i < n; ++i) {
            int val = nums[i];
            if (prev2[val] != -1) {
                minDistance = min(minDistance, 2 * (i - prev2[val]));
            }
            prev2[val] = prev1[val];
            prev1[val] = i;
        }

        return minDistance == INT_MAX ? -1 : minDistance;
    }
};

/**
 * Problem: LeetCode 3741 - Minimum Distance Between Three Equal Elements II
 * Difficulty: Medium
 * Language: JavaScript
 * Author: CodeByTushu
 */
/**
 * @param {number[]} nums
 * @return {number}
 */
var minimumDistance = function(nums) {
    const n = nums.length;
    const prev1 = new Int32Array(n + 1);
    const prev2 = new Int32Array(n + 1);
    prev1.fill(-1);
    prev2.fill(-1);

    let minDistance = Infinity;

    for (let i = 0; i < n; i++) {
        const val = nums[i];
        if (prev2[val] !== -1) {
            const dist = 2 * (i - prev2[val]);
            if (dist < minDistance) {
                minDistance = dist;
            }
        }
        prev2[val] = prev1[val];
        prev1[val] = i;
    }

    return minDistance === Infinity ? -1 : minDistance;
};