diff options
Diffstat (limited to 'count_num_good_subarr.py')
-rw-r--r-- | count_num_good_subarr.py | 35 |
1 files changed, 35 insertions, 0 deletions
diff --git a/count_num_good_subarr.py b/count_num_good_subarr.py new file mode 100644 index 0000000..69eedce --- /dev/null +++ b/count_num_good_subarr.py @@ -0,0 +1,35 @@ +# 2537. Count the Number of Good Subarrays +from collections import Counter + +""" +given an integer array 'nums' and an integer 'k', return the number of good +subarrays of 'nums'. a subarray 'arr' is good if there are at least 'k' pairs +of indices '(i, j)' such that 'i < j' and 'arr[i] == arr[j]'. a subarray is a +contiguous non-empty sequence of elements within an array. +""" + + +class Solution(object): + def countGood(self, nums, k): + """ + :type nums: List[int] + :type k: int + :rtype: int + """ + ans, i = 0, 0 + cnt = Counter() + for j in range(len(nums)): + k -= cnt[nums[j]] + cnt[nums[j]] += 1 + while k <= 0: + cnt[nums[i]] -= 1 + k += cnt[nums[i]] + i += 1 + ans += i + return ans + + +if __name__ == "__main__": + obj = Solution() + print(obj.countGood(nums=[1, 1, 1, 1, 1], k=10)) + print(obj.countGood(nums=[3, 1, 4, 3, 2, 2, 4], k=2)) |