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Practice Positions of Large Groups

Read the task, work through the examples, and check your approach against the constraints. Use the original LeetCode task for coding and submissions.

Easy#830
LeetCode Problem

Positions of Large Groups

String

Problem Statement

In a string s of lowercase letters, these letters form consecutive groups of the same character. For example, a string like s = "abbxxxxzyy" has the groups "a", "bb", "xxxx", "z", and "yy". A group is identified by an interval [start, end], where start and end denote the start and end indices (inclusive) of the group. In the above example, "xxxx" has the interval [3,6]. A group is considered large if it has 3 or more characters. Return the intervals of every large group sorted in increasing order by start index.

Source: Positions of Large Groups on LeetCode. Use the original task for its coding environment and submissions.

Examples

# Example 1

Input
s = "abbxxxxzzy"
Output
[[3,6]]

# Example 2

Input
s = "abc"
Output
[]

# Example 3

Input
s = "abcdddeeeeaabbbcd"
Output
[[3,5],[6,9],[12,14]]

Constraints

1 <= s.length <= 1000
s contains lowercase English letters only.

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