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4115 Minimum Distance Between Three Equal Elements I

4115 Minimum Distance Between Three Equal Elements I

Minimum Distance Between Three Equal Elements I image

You are given an integer array nums.

A tuple (i, j, k) of 3 distinct indices is good if nums[i] == nums[j] == nums[k].

The distance of a good tuple is abs(i - j) + abs(j - k) + abs(k - i), where abs(x) denotes the absolute value of x.

Return an integer denoting the minimum possible distance of a good tuple. If no good tuples exist, return -1.

 

Example 1:

Input: nums = [1,2,1,1,3]

Output: 6

Explanation:

The minimum distance is achieved by the good tuple (0, 2, 3).

(0, 2, 3) is a good tuple because nums[0] == nums[2] == nums[3] == 1. Its distance is abs(0 - 2) + abs(2 - 3) + abs(3 - 0) = 2 + 1 + 3 = 6.

Example 2:

Input: nums = [1,1,2,3,2,1,2]

Output: 8

Explanation:

The minimum distance is achieved by the good tuple (2, 4, 6).

(2, 4, 6) is a good tuple because nums[2] == nums[4] == nums[6] == 2. Its distance is abs(2 - 4) + abs(4 - 6) + abs(6 - 2) = 2 + 2 + 4 = 8.

Example 3:

Input: nums = [1]

Output: -1

Explanation:

There are no good tuples. Therefore, the answer is -1.

 

Constraints:

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2
1 <= n == nums.length <= 100
1 <= nums[i] <= n
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class Solution:
    def minimumDistance(self, nums: List[int]) -> int:
        # if i sort these on nums and then on index
        # then i slide a window of len 3
        # and calculate the dist
        if len(nums) < 3:
            return -1
        arr =  []
        for (i, k) in enumerate(nums):
            arr.append((k,i))

        arr.sort(key = lambda x : (x[0], x[1]))
        print(arr)
        res = 1000000
        left =  0
        right = 2
        while(right < len(arr)):
            if arr[left][0] == arr[left + 1][0] and arr[left+1][0] == arr[right][0]:
                res = min(res, abs(arr[left][1] - arr[left + 1][1]) + abs(arr[left + 1][1] - arr[left + 2][1]) + abs(arr[left + 2][1] - arr[left][1]))
            right += 1
            left += 1
        return -1 if res == 1000000 else res







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