My software development journey
Given an array of numbers, how to find the maximum length of increasing (non-decreasing) continuous sub-sequence? For example consider the array [7, 9, 1, 3, 5, 8, 2], the maximum length is 4. Similarly for [23, 10, 18, 18, 6], it is 3. This is a straight forward implementation problem (appeared on Codeforces). Following is…
Given an array of numbers and a sum, how to check if there is any sub-array with the given sum. For example consider an array A = [7, 2, 9, 1, 5], and the sum is 12, then we can find a sub-array [2, 9, 1] which sums up to 12. So the answer is…
Given a number K, Find the shortest and smallest string which has K positions in it, such that the character at that position is alphabetically greater than the character immediately after it. Only the lower case alphabets [a-z] are allowed. For example consider K = 1 “ba” is the shortest and smallest string possible. There…
Given an array of numbers A[N], how do we arrange them in the following order. A[0] <= A[1] >= A[2] <= A[3]…A[N-1] For example consider the array A =[6, 9, 36, 24, 42] The answer can be [6, 36, 9, 42, 24]. There can be multiple answers also like [6, 42, 9, 36, 24]. We…
Given two arrays of numbers, how to check if the first sequence is a sub sequence of second sequence.For example [3, 7, 11] is a sub-sequence of [9, 3, 1, 7, 5, 11]where as [4, 8, 9] is not a sub-sequence of [6, 4, 9, 2, 8]The algorithm here is simple. Let us assume two…
Given a rectangle of some length and width, How do you divide them into minimum number of squares? This is a problem from Codechef.For example give a rectangle of size 2 x 4, we can make them into two squares of 2 x 2.Similarly a rectangle of size 3 x 7, can only be divided…
Given a permutation of numbers from 1 to N, We can represent it in two ways. For example, let us consider a permutation from 1 to 5 P = [2 4 1 5 3] This representation directly indicates the position of each number. i.e 2 is first, 4 is second and so on. Alternatively, this…
Given an array of elements, how do we find the XOR of each sub-array and XOR of those results? For example let us consider the array [1, 2, 3], all possible sub-arrays are XOR[1] = 1XOR[1, 2] = 1 ^ 2 = 3XOR[1, 2, 3] = 1 ^ 2 ^ 3 = 0XOR[2] = 2XOR[2,…
Given a string, We have to find out by removing which character, it becomes a palindrome.For example consider the string “racercar”, the character ‘r’ at index 4 should be removed to become a palindrome.The approach here is simple. Start from both ends of the string and compare both characters. If they are equal, we increment…
Radix sort is an integer sorting algorithm. As it’s name indicates, it sorts a list of numbers based on the digits of the numbers. It’s a linear time sorting algorithm which is different from the comparison based sorting algorithms like quick sort or heap sort. Counting sort is also a linear time sorting algorithm which…