Reconstruct Original Digits From English

To solve this coding challenge, we need to extract and reconstruct the original digits (0-9) from a scrambled string of English words that represent these digits. The goal is to return these digits in ascending order.

Explanation

Let's break down the problem and its solution step-by-step. The provided string contains jumbled representations of English words for digits 0 through 9. Each digit has a unique letter or a combination of letters that can help us identify its presence in the scrambled string. For example:
  • The word "zero" contains the unique letter 'z'.
  • The word "two" contains the unique letter 'w'.
  • The word "four" contains the unique letter 'u'.
  • And so forth...
The strategy involves counting occurrences of these unique characters to determine the frequency of each digit, then updating the counts by accounting for overlapping characters across various digits.

Step-by-Step Explanation:

  1. Count Frequency of Letters : Use a hash map to count the frequency of each character in the scrambled string.
  2. Identify Unique Digits : Use the unique characters that appear in only one digit's word to determine the initial counts of those unique digits.
  3. Adjust for Overlapping Characters : Once the unique digits are counted, adjust counts for the remaining digits that share characters by subtracting the counts of already identified digits.
  4. Reconstruct Digit String : Finally, construct the resulting number string from the digit counts in ascending order.
  5. Detailed Steps in Pseudocode:
  6. Count Frequency of Letters :
  7.                                             
    # Create an empty hash map to store character counts
    char_count = {}
    
    # Iterate over each character in the string s and update the hash map
    for each character in s:
    if character in char_count:
    char_count[character] += 1
    else:
    char_count[character] = 1
    
                                            
  8. Identify Unique Digits Based on Unique Letters :
  9.                                             
    # Create an array to store counts of each digit from 0 to 9
    digit_counts = array of size 10 initialized to 0
    
    # Identify counts for digits with unique determining letters
    digit_counts[0] = char_count['z']  # "zero" has unique 'z'
    digit_counts[2] = char_count['w']  # "two" has unique 'w'
    digit_counts[4] = char_count['u']  # "four" has unique 'u'
    digit_counts[6] = char_count['x']  # "six" has unique 'x'
    digit_counts[8] = char_count['g']  # "eight" has unique 'g'
    
                                            
  10. Adjust for Overlapping Characters :
  11.                                             
    # Adjust counts for other digits by subtracting already known counts
    digit_counts[3] = char_count['h'] - digit_counts[8]  # "three" has shared 'h' with "eight"
    digit_counts[5] = char_count['f'] - digit_counts[4]  # "five" has shared 'f' with "four"
    digit_counts[7] = char_count['s'] - digit_counts[6]  # "seven" has shared 's' with "six"
    digit_counts[9] = char_count['i'] - digit_counts[5] - digit_counts[6] - digit_counts[8]  # "nine" has shared 'i' with "five", "six", and "eight"
    digit_counts[1] = char_count['n'] - (2 * digit_counts[9]) - digit_counts[7]  # "one" has shared 'n' with "nine" and "seven"
    
                                            
  12. Reconstruct and Return the Result :
                                            
# Initialize an empty string for result
result = ""

# Construct the resulting digits string by iterating from 0 to 9
for i from 0 to 9:
    append digit i, digit_counts[i] times to result

# Return the reconstructed string containing digits in ascending order
return result

                                        
By carefully following these steps and leveraging the uniqueness of certain letters in the words representing digits, we can reconstruct the original sequence of digits from the given scrambled string efficiently and accurately.