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Leetcode
Medium
Arrays
Intervals
Summary Ranges
Compress a sorted list of integers into compact range strings.
Acceptance 0%
Problem Statement
You are given a sorted array of integers with no duplicates. Group consecutive values into ranges and represent each range as a string.
- A single number should be written as just that number.
- A consecutive run of length at least 2 should be written as
start->end.
Return the list of range strings in the same order as the numbers appear.
Input Format
- An integer array
nums. numsis sorted in strictly increasing order.
Output Format
- Return an array of strings describing the consecutive ranges in
nums.
Constraints
numsis sorted in strictly increasing order.- Adjacent elements may differ by 1 or more.
- Use 32-bit signed integers for values.
Examples
Sample cases returned by the problem API.
Example 1
Input
nums = [0,1,2,4,5,7]
Output
["0->2","4->5","7"]
Explanation
The consecutive groups are [0,1,2], [4,5], and [7].
Example 2
Input
nums = [0,2,3,4,6,8,9]
Output
["0","2->4","6","8->9"]
Explanation
Only adjacent numbers are merged into a range.
Show 1 more example
Example 3
Input
nums = []
Output
[]
Explanation
An empty array produces no ranges.
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