C++ Articles - Page 538 of 719

Consider we have a list of numbers; our task is to find the middle of the linked list using recursion. So if the list elements are [12, 14, 18, 36, 96, 25, 62], then the middle element is 36.To solve this problem, we will count total number of nodes in the list in recursive manner and do half of this. Then rolling back through recursion decrement n by 1 in each call, return element where n is zero.Example#include #include using namespace std; class Node{    public:       int data;       Node *next; }; Node* getNode(int data){ ... Read More

Consider we have a matrix, our task is to find the maximum element of each row of that matrix and print them. This task is simple. For each row, reset the max, and find the max element, and print it. Let us see the code for better understanding.Example#include #define MAX 10 using namespace std; void largestInEachRow(int mat[][MAX], int rows, int cols) {    for (int i = 0; i < rows; i++) {       int max_row_element = mat[i][0];    for (int j = 1; j < cols; j++) {       if (mat[i][j] > max_row_element)          max_row_element = mat[i][j];    }    cout

Consider we have a matrix, our task is to find the maximum element of each column of that matrix and print them. This task is simple. For each column, reset the max, and find the max element, and print it. Let us see the code for better understanding.Example#include #define MAX 10 using namespace std; void largestInEachCol(int mat[][MAX], int rows, int cols) {    for (int i = 0; i < cols; i++) {       int max_col_element = mat[0][i];    for (int j = 1; j < rows; j++) {       if (mat[j][i] > max_col_element)          max_col_element = mat[j][i];    }    cout

Suppose we have a string str. We have another character ch. Our task is to find the last index of ch in the string. Suppose the string is “Hello”, and character ch = ‘l’, then the last index will be 3.To solve this, we will traverse the list from right to left, if the character is not same as ‘l’, then decrease index, if it matches, then stop and return result.Example#include using namespace std; int getLastIndex(string& str, char ch) {    for (int i = str.length() - 1; i >= 0; i--)       if (str[i] == ch)   ... Read More

Consider we have one circular array containing integers from 1 to n. Find the last element, that would remain in the list after deleting every second element starting from first element. If the input is 5, then array will be [1, 2, 3, 4, 5]. Start from 1. After deleting each second element will be like −1 0 3 4 5 1 0 3 0 5 0 0 3 0 5 0 0 3 0 0So the element that remains in the list is 3.We will solve this problem using recursion. Suppose n is even. The numbers 2, 4, 6 ... Read More

Consider we have a dictionary, and a string s. Find the longest string in the dictionary, that can be formed by deleting some characters of the string s. Suppose the s is “apbreoigroakml”, The dictionary has {“prog”, “ram”, “program”}, then the result will be “program”.To solve this, we will traverse all dictionary words, and for each word, we will check whether the subsequence of the given string and is longest of all such words. Finally return longest word with given string as subsequence.Example#include #include using namespace std; bool isSubSequence(string s1, string s2) {    int m = s1.length(), n = ... Read More

Suppose we have an array A with some elements. We have to find the largest element in the array A, but the constraint is, we cannot use any conditional operator. So if A = [12, 63, 32, 24, 78, 56, 20], then maximum element will be 78.To solve this problem, we will use the bitwise AND operation. at first we will insert one extra element INT_MAX (where all bit is 1) in array. Then we will try to find maximum AND value of any pair from the array. This obtained max value will contain AND value of INT_MAX and largest ... Read More

Consider we have an array A with few elements. The array is unsorted. We have two other value X and k. Our task is to find the k number of nearest elements of X from the array A. If the element X is present in the array, then it will not be shown in the output. If A = [48, 50, 55, 30, 39, 35, 42, 45, 12, 16, 53, 22, 56] and X = 35, k = 4. The output will be 30, 39, 42, 45.To solve this, we will use the heap data structure. The steps will be ... Read More

Consider we have an array A with few elements. We have two other value X and k. Our task is to find the k number of nearest elements of X from the array A. If the element X is present in the array, then it will not be shown in the output. If A = [12, 16, 22, 30, 35, 39, 42, 45, 48, 50, 53, 55, 56] and X = 35, k = 4. The output will be 30, 39, 42, 45.To solve this, we will use the binary search approach. Using this we will get the crossover point. ... Read More

Suppose we have a number N. We have another number k. We have to check the number can be represented using k numbers or not. Suppose a number 54, and k = 3, then it will print the numbers like [2, 3, 9], if it cannot be represented, then print that.To solve this, we will find all prime factors of N, and store them into a vector, then to find k numbers greater than 1, we check the size of the vector is greater than k or not. If size is less than k, then return -1, otherwise print first ... Read More