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# Q1. 1534. Count Good Triplets

Given an array of integers arr, and three integers a, b and c. You need to find the number of good triplets.

A triplet (arr[i], arr[j], arr[k]) is good if the following conditions are true:

0 <= i < j < k < arr.length
|arr[i] - arr[j]| <= a
|arr[j] - arr[k]| <= b
|arr[i] - arr[k]| <= c
Where |x| denotes the absolute value of x.

Return the number of good triplets.

## Note

From constrain `3 <= arr.length <= 100`, we know this can be solved by `complete search` aka `Brute force`

# Q2. 1535. Find the Winner of an Array Game

Given an integer array arr of distinct integers and an integer k.

A game will be played between the first two elements of the array (i.e. arr and arr). In each round of the game, we compare arr with arr, the larger integer wins and remains at position 0 and the smaller integer moves to the end of the array. The game ends when an integer wins k consecutive rounds.

Return the integer which will win the game.

It is guaranteed that there will be a winner of the game.

## Note

Stuck here for a long time.
Key point is once we have visited the entire array once, the greatest number will be kept at idx-0.
Hence, we can simply simulate the game and find the first number win k times.

# 3. 1536. Minimum Swaps to Arrange a Binary Grid

## Note

After you realize that this question is about permutation of array, it is not that hard.
Convert matrix into array of numbers by counting the length of continuous `0` from right side.

# Q4. 1537. Get the Maximum Score FAILED

## Note

I thought this must be a DP problem hence we can easily tell how the state is transit from previous state.

2. Surprisingly, `@lru_cache` cause MLE while native dictionary works.