How to Solve Reformat Phone Number Problem
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Reformat Phone Number
You are given a phone number as a string number. number consists of digits, spaces ' ', and/or dashes '-'. You would like to reformat the phone number in a certain manner. Firstly, remove all spaces a...
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Understanding the Reformat Phone Number Problem
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Problem Statement
You are given a phone number as a string number. number consists of digits, spaces ' ', and/or dashes '-'. You would like to reformat the phone number in a certain manner. Firstly, remove all spaces and dashes. Then, group the digits from left to right into blocks of length 3 until there are 4 or fewer digits. The final digits are then grouped as follows: 2 digits: A single block of length 2. 3 digits: A single block of length 3. 4 digits: Two blocks of length 2 each. The blocks are then joined by dashes. Notice that the reformatting process should never produce any blocks of length 1 and produce at most two blocks of length 2. Return the phone number after formatting.
Reformat Phone Number
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Examples
number = "1-23-45 6""123-456"The digits are "123456". Step 1: There are more than 4 digits, so group the next 3 digits. The 1st block is "123". Step 2: There are 3 digits remaining, so put them in a single block of length 3. The 2nd block is "456". Joining the blocks gives "123-456".
number = "123 4-567""123-45-67"The digits are "1234567". Step 1: There are more than 4 digits, so group the next 3 digits. The 1st block is "123". Step 2: There are 4 digits left, so split them into two blocks of length 2. The blocks are "45" and "67". Joining the blocks gives "123-45-67".
number = "123 4-5678""123-456-78"The digits are "12345678". Step 1: The 1st block is "123". Step 2: The 2nd block is "456". Step 3: There are 2 digits left, so put them in a single block of length 2. The 3rd block is "78". Joining the blocks gives "123-456-78".
Constraints
2 <= number.length <= 100number consists of digits and the characters '-' and ' '.There are at least two digits in number.How Interview Coder Helps with Leetcode Problems
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