Maximum XOR value of two elements

Given an array of numbers find the maximum XOR value of two numbers in the array. Input Array = {12, 15, 5, 1, 7, 9, 8, 6, 10, 13}; Output = 15 (XOR of 5 and 10) 5 = 0101 10 = 1010 ——— XOR = 1111

Rectangles in a matrix

Given a character matrix in which some of the cells have alphabets written on them while other cells are empty (empty cells contains character ‘-‘ in them). For example consider the below matrix: A – – – B – – – C All characters are unique. Set character on all empty cells in such a […]

Sum of rectangle region in a given matrix

Given a matrix of integers of order M*N and coordinates of a rectangular region in the matrix, write code to find the sum of all the elements in that rectangular region. For example, if the input matrix is And co-ordinated given are (3,4) and (6, 8), then they represent the below rectangular region whose Sum […]

Putting blocks at largest distance from each other in a row

Given a row (linear), two blocks are placed at each end and there are n empty positions between then. If ‘B’ represent block and n = 9 then the row looks like below: B _ _ _ _ _ _ _ _ _ B One blocks can be placed on each empty position. k blocks […]

Nearest number with non-decreasing digits

Given a number N given in the form of array, with each index storing one digit of the number. Write code to change the number to the greatest number less than N, such that digits of that number are in non-decreasing order. For example: INPUT ARRAY: {1, 4, 3} (representing number 143) OUTPUT : 139 […]

Flip all zeros to ones

Given a string of bits and a number k. In one flip, you can toggle k consecutive characters, how many flips are required to change the entire string to all ones. For example Input String: 0000110000 k: 3 OUTPUT: 4 Following are the four flips: FLIP-1: 1110110000 FLIP-2: 1110110111 FLIP-3: 1111000111 FLIP-4: 1111111111 If it is not possible […]

Print permutations of string replaced with digits

Given a string, print the variation of string as shown below Input String: ‘hat’ Replace one character with numeric one(‘1’): ‘1at‘, ‘h1t‘, ‘ha1‘ Replace two characters with ‘1’ each: ‘11t‘, ‘h11‘, ‘1a1‘ Replace three characters with ‘1’ each: ‘111‘ In all the strings above, wherever the numeric characters are consecutive, add them. So ’11t’ will become ‘2t’, Similarly ‘111’ […]

Check if two arrays are permutation of each other

Given two arrays of integers, write a code to check if one is permutation (arranging the same numbers differently) of elements present in the other. For example, the below two arrays are permutations of each other: int a[5] = {1, 2, 3, 4, 5}; int b[5] = {2, 1, 4, 5, 3};

Rearrange array into alternate positive and negative numbers

Given an array containing both positive and negative integers, write code to rearrange the elements so that positive and negative numbers comes alternately. If positive (or negative) integers is not equal in number then extra positive (or negative) numbers should come at the end of array. For example: Input : {1, 2, -2, -5, 6, […]

Array implementation of Stack

A better implementation of Stack is usually using linked list unless you are sure of the number of elements in array. But if you are just starting with data structures and are not familiar with linked list, you can try implementing stack in an array. While using array to implement stack is easy, it has limitation that […]