Topic: hashing-problem / Level: beginner

• 51. Implement a function to return the first unique character in a string using a hash map.
• 52. Write a program to find the maximum length of a subarray with distinct elements using hashing.
• 53. Create a function that returns the number of distinct characters in a string using a hash set.
• 54. Given a list of names, write a function to find the names that appear more than once using hashing.
• 55. Write a program to check if the characters in a string can form a palindrome using a hash map.
• 56. Create a function to find the frequency of the first character in a string using hashing.
• 57. Implement a program to return the characters that do not appear in another string using hashing.
• 58. Write a function to find the sum of all unique elements in an array using a hash set.
• 59. Create a function that checks if two strings are made of the same characters using a hash table.
• 60. Given an integer, write a program to return the count of its prime factors using hashing.
• 61. Write a function to count the number of uppercase and lowercase letters in a string using hashing.
• 62. Create a program that returns the first non-repeating character in a string using a hash map.
• 63. Implement a function to find the maximum element that occurs more than once in an array using hashing.
• 64. Write a program to find the frequency of each consonant in a string using a hash map.
• 65. Create a function that checks if the elements in an array are in a specific range using a hash set.
• 66. Given a string, write a program to find the shortest substring containing all unique characters using hashing.
• 67. Implement a function to return the indices of all occurrences of a character in a string using a hash map.
• 68. Write a program to find the first character that appears twice in a string using hashing.
• 69. Create a function to find the longest substring with at least k repeating characters using hashing.
• 70. Given two strings, write a function to determine if one string can be made by rearranging the other using hashing.
• 71. Write a program to count the number of times a specific character appears in a string using hashing.
• 72. Create a function that checks if two arrays contain the same elements but in different orders using hashing.
• 73. Implement a function to find the longest substring that contains two distinct characters using hashing.
• 74. Write a program to find the total number of characters in a string excluding duplicates using a hash set.
• 75. Create a function that returns the frequency of the first 10 digits in a number using hashing.
• 76. Given a list of integers, write a program to determine if any three numbers can form a triangle using hashing.
• 77. Write a function to find the longest common prefix among a set of strings using a hash table.
• 78. Create a program that checks if a string can be formed from another string by removing characters using hashing.
• 79. Implement a function to count the number of occurrences of each word in a sentence using a hash map.
• 80. Write a program to check if a string is a valid IP address using hashing.
• 81. Create a function to determine if a given number is a happy number using hashing.
• 82. Given a list of words, write a function to find the longest word that can be formed using characters from another word using hashing.
• 83. Write a program to count the total number of characters in a string ignoring spaces using hashing.
• 84. Create a function that checks if two strings are anagrams of each other by sorting and comparing hashes.
• 85. Implement a function to find the longest substring of unique characters in a string using a hash set.
• 86. Write a program to find the number of valid email addresses in a list using hashing.
• 87. Create a function that checks if an array can be partitioned into two subsets with equal sums using hashing.
• 88. Given a string, write a function to find the longest substring with all distinct vowels using hashing.
• 89. Write a program to find the minimum character swaps required to make two strings anagrams using hashing.
• 90. Create a function that returns the indices of all occurrences of a character in a string using a hash map.
• 91. Implement a function to determine if two strings are rotations of each other using hashing.
• 92. Write a program to find the number of times a word appears in a text using hashing.
• 93. Create a function that checks if a string has balanced brackets using a hash map.
• 94. Given a list of integers, write a program to determine if any two numbers add up to a specific sum using hashing.
• 95. Write a function to count the number of unique elements in an array using a hash set.
• 96. Create a program to find the maximum product of any two distinct numbers in an array using hashing.
• 97. Implement a function to check if a string is a valid anagram of a palindrome using a hash map.
• 98. Write a program to find the longest substring with at most two distinct characters using hashing.
• 99. Create a function that counts the occurrences of each digit in a number using hashing.
• 100. Given a string, write a function to find the longest substring of digits using hashing.

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