C Articles - Page 105 of 134

A tetrahedron is a pyramid with triangular base i.e. it has a base that is a triangle and each side has a triangle. All the three triangles converge to a point. As in the figure, Code Logic − The code to find the area and volume of tetrahedron uses the math library to find the square and square-root of a number using sqrt and pow methods. For calculating the area we take a floating point and the value of the expression “((sqrt(3)*a*a))” is given to it. Another variable get the value of volume of the tetrahedron that is evaluated by ... Read More

Trapezium is a type of quadrilateral that has at least one pair of side parallel to each other. Area and perimeter of a trapezium can be found using the below formula, Perimeter = sum of all sidesArea = ½ x (sum of the lengths of the parallel sides) x perpendicular distance between parallel sidesCode logic − The code will use 5 variables in as all sides of trapezium and one for the perpendicular distance between the two parallel side. For the area variable calculation we will take a float variable that will be initialised with the value. To calculate it ... Read More

Tringle is a closed figure with three sides. An equilateral triangle has all sides equal. Area and perimeter of an equilateral triangle can be found using the below formula, Area of equilateral triangle = (√3)/4*a2Perimeter of equilateral triangle = 3 * aLogic of CodeTo find the area of an equilateral triangle program uses square-root and power functions. The math library has both these functions and can be used to do the calculation in the program.The below code display program to calculate the area and perimeter of an equilateral triangle, Example Live Demo#include #include int main(){    int side = ... Read More

Rhombus is a simple quadrilateral whose four sides all have the same length. And perimeter of rhombus can be found by two methods.Adding all side.Using the diagonalsA quadrilateral has two diagonal and based on the length of diagonals the area and perimeter of the quadrilateral can be found.To find the perimeter of a rhombus using its diagonals is 2{√(d1)2 + (d2)2 }LOGIC − To find the perimeter of a rhombus using its diagonals. You need the formula 2{√(d1)2 + (d2)2 } for this in your code you need to use the math class that supports the use of squareRoot and ... Read More

It is basically pointless to check for a NULL pointer before deleting. Deleting a pointer will do nothing if the pointer set to NULL. It might be the reason to check for the NULL pointer that deleting a pointer which is already set to NULL may indicate bugs in the program.

In C++, a null pointer can be defined by as a null pointer constant is an integer constant expression with the value 0, like −int*p = 0;But in c, a null pointer can be defined by as a null pointer constant is an integer constant expression with the value 0 or such an expression cast to void*, like −Int *p = 0;;Orint*p = (void*) 0;In C++11 a keyword “nullptr” is used to represent nullpointer.int* ptr = nullptr;In CExample Live Demo#include int main() {    int *p= NULL; //initialize the pointer as null.    printf("The value of pointer is %u", p); ... Read More

The void pointer is a pointer which is not associate with any data types. It points to some data location in storage means points to the address of variables. It is also called general purpose pointer. Is It Safe to Delete a Void Pointer in C/C++? It is not safe to delete a void pointer in C/C++ because delete needs to call the destructor of whatever object it's destroying, and it is impossible to do that if it doesn't know the type. C Example of Void Pointer In this example, a void pointer (void *p) can store the address of ... Read More

A pointer is used to store the address of the variables. To declare pointer variables in C/C++, an asterisk (*) used before its name.Declaration*pointer_nameIn CExample Live Demo#include int main() {    // A normal integer variable    int a = 7;    // A pointer variable that holds address of a.    int *p = &a;    // Value stored is value of variable "a"    printf("Value of Variable : %d", *p);    //it will print the address of the variable "a"    printf("Address of Variable : %p", p);    // reassign the value.    *p = 6;    printf("Value ... Read More

The pointers can be directly compared using relational operators. In this article, we will learn about the comparisons of the pointers with the help of examples. Pointers Comparison in C and C++ In C/C++, we can directly compare the pointers using relational operators (==, !=, , =). These operators are used to compare two variables, values, or pointers. It returns a Boolean true value when the comparison is correct otherwise, it is false. The core syntaxes of C and C++ pointers are similar such as declaration, dereferencing, and pointer arithmetic. All of these are identical in behavior and still use ... Read More

Function Pointers point to code like normal pointers.In Functions Pointers, function’s name can be used to get function’s address.A function can also be passed as an arguments and can be returned from a function.Declarationfunction_return_type(*Pointer_name)(function argument list)Example Live Demo#include int subtraction (int a, int b) {    return a-b; } int main() {    int (*fp) (int, int)=subtraction;    //Calling function using function pointer    int result = fp(5, 4); printf(" Using function pointer we get the result: %d",result); return 0; }OutputUsing function pointer we get the result: 1