Topic: array-problem / Level: beginner

• 51. Find the column in a 2D array with the highest sum of elements.
• 52. Find the transpose of a 2D array.
• 53. Check if two arrays are disjoint (i.e., have no common elements).
• 54. Find the median of an array.
• 55. Count the number of elements greater than or equal to a given value x in an array.
• 56. Find the maximum element in each row of a 2D array.
• 57. Find the maximum element in each column of a 2D array.
• 58. Find the minimum element in each row of a 2D array.
• 59. Find the minimum element in each column of a 2D array.
• 60. Sort the elements of each row in a 2D array in ascending order.
• 61. Find the sum of all elements in the upper triangular part of a 2D matrix.
• 62. Find the sum of all elements in the lower triangular part of a 2D matrix.
• 63. Check if a given array is symmetric.
• 64. Merge two unsorted arrays and sort the resulting array.
• 65. Find the common elements between two arrays.
• 66. Find the union of two unsorted arrays without using built-in functions.
• 67. Find the intersection of two unsorted arrays without using built-in functions.
• 68. Remove all negative numbers from an array.
• 69. Insert a new element at a given position in an array.
• 70. Delete an element at a given position from an array.
• 71. Replace all occurrences of a specific element in an array with another element.
• 72. Split an array into two equal halves.
• 73. Find the largest sum of any contiguous subarray (Kadanes algorithm for beginners).
• 74. Reverse each row of a 2D array.
• 75. Check if an array contains only positive numbers.
• 76. Count how many times each distinct element appears in an array.
• 77. Find the sum of the first n natural numbers stored in an array.
• 78. Remove all zeros from an array and shift non-zero elements to the front.
• 79. Find the cumulative sum of the elements in an array.
• 80. Check if all elements in an array are either odd or even.
• 81. Find the longest contiguous subarray with alternating odd and even elements.
• 82. Find the product of the elements in the first half of an array.
• 83. Calculate the running average of all elements in an array.
• 84. Print the elements of an array in reverse order without modifying the original array.
• 85. Find the number of elements in an array that are greater than their immediate neighbors.
• 86. Find the largest element in an array that is smaller than a given number x.
• 87. Find the smallest element in an array that is greater than a given number x.
• 88. Swap the even-indexed elements with the odd-indexed elements of an array.
• 89. Find the difference between the largest and smallest elements in an array.
• 90. Find the smallest positive missing number in an array.
• 91. Find the average of the elements in each column of a 2D array.
• 92. Multiply two 2D matrices together.
• 93. Check if a 2D array is a magic square (where sums of rows, columns, and diagonals are equal).
• 94. Find the trace of a square matrix (sum of diagonal elements).
• 95. Flatten a 2D array into a 1D array.
• 96. Reverse the diagonal elements of a 2D array.
• 97. Check if an array of strings contains any palindromes.
• 98. Find the difference between the maximum and minimum elements of each row in a 2D array.
• 99. Find the largest element in an array that is smaller than the average of all elements.
• 100. Calculate the sum of the absolute differences of consecutive elements in an array.

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• Intermediate
• Advanced