The size of an empty class is not zero in C++ as it allocates one unique address to the object in the memory. The size can not be 0, because the two classes can not have the same memory address. So, the size of an empty class is 1 byte which does not hold any data, it is just for memory allocation. In this article, we will see an example of checking the size of an object of an empty class in C++. Demonstrating Size of an Empty Class In this approach, we have two C++ classes. One class ... Read More

In this section we will discuss about where the variables and objects are stored in the memory when a C++ program is compiled. As we know, there are two parts of memory in which an object can be stored −Stack − All members that are declared inside block of memory, it stores inside the stack section. The main function is also a function, so elements inside it will be stored inside the stack.Heap − When some objects are allocated dynamically, then that is stored inside the heap section.The scope of the object declared inside a block or a function is ... Read More

In this section we will discuss about interesting facts restrictive access of derived class methods in C++. We will see some examples and analyze the output to know more about restrictions of using derived class methods in C++.Example (C++)Let us see the following implementation to get better understanding −#include using namespace std; class BaseClass { public:    virtual void display(){       cout

In this section we will discuss about interesting facts about virtual classes in C++. We will see two cases first, then we will analyze the fact.At first execute the program without using any virtual function.The execute the program using any virtual function under non-virtual function.ExampleLet us see the following implementation to get better understanding − Live Demo#include using namespace std; class BaseClass { public:    void display(){       cout

Suppose we have given function like f(x) = (x^6 + x^2 + 9894845) % 971, now for a given value of x, we have to find the value of f(x).So, if the input is like 5, then the output will be 469To solve this, we will follow these steps −Define a function power_mod(), this will take base, exponent, modulus, base := base mod modulusresult := 1while exponent > 0, do −if exponent is odd, then −result := (result * base) mod modulusbase := (base * base) mod modulusexponent = exponent /2return resultFrom the main method do the following −return power_mod(n, ... Read More

Suppose we have a string, s, and we have another list with few words, these words are of same length. We have to find all starting indices of substring(s) in s that is a concatenation of each word in words exactly once and without any intervening characters.So if the input is like “wordgoodgoodgoodword” and words are ["word", "good"], then the output will be [0, 12]. This is because the substring starting at index 0 and 12 are “wordgood” and “goodword”.To solve this, we will follow these steps −Define a method called ok(), this will take string s, map wordCnt and ... Read More

Suppose we have a given weighted undirected graph with N different nodes and M edges, some of the nodes are good nodes. We have to find the shortest distance between any pair of two different good nodes. In the given diagram the yellow in the following graph are considered to be good nodes.So, if the input is likethen the output will be 11, as the pairs of good nodes and distance between them are: (1 to 3) the distance is 11, (3 to 5) the distance is 13, (1 to 5) the distance is 24, out of which 11 is ... Read More

Suppose we have a number N this represents the initial position of the person on the number line. We also have L which is the probability of the person of going left. We have to find the the probability of reaching all points on the number line after completing N moves from point N. Each move can be either to the left or to the right.So, if the input is like n = 2, l = 0.5, then the output will be [0.25, 0, 0.5, 0, 0.25]To solve this, we will follow these steps −high := 1 - lowDefine an ... Read More

Suppose we have width and height of N different rectangles; we have to find the minimum number of rectangles left after inserting one into another. So, if W1 and W2 be the width of rectangles R1 and R2 respectively. And H1 and H2 be the height of R1 and R2 respectively, then if W1 < W2 and H1 < H2 then rectangle R1 fits inside rectangle R2. Thus, the smallest one can fit into second smallest, then that fits into the next and so on.So, if the input is like {{ 30, 45 }, { 15, 15 }, { 45, ... Read More

Suppose we have an array of pairs A; we have to find the maximum cost for selecting at most K pairs. In this case, the cost of an array of pairs type elements is the product of the sum of first elements of the selected pair and the smallest among the second elements of the selected pairs. As an example, if these pairs are selected (4, 8), (10, 3) and (3, 6), then the cost will be (4+10+3)*(3) = 51, for K=3So, if the input is like A = [(15, 5), (65, 25), (35, 20), (20, 5), (35, 20), (15, ... Read More