Happy Codings - Programming Code Examples
Html Css Web Design Sample Codes CPlusPlus Programming Sample Codes JavaScript Programming Sample Codes C Programming Sample Codes CSharp Programming Sample Codes Java Programming Sample Codes Php Programming Sample Codes Visual Basic Programming Sample Codes


C++ Programming Code Examples

C++ > Computer Graphics Code Examples

Program to Implement B-Tree

/* Program to Implement B-Tree This C++ program implements the B-Tree data structure. B-tree is a tree data structure that keeps data sorted and allows searches, sequential access and insertions in logarithmic time. The B-tree is a generalization of a binary search tree in that a node can have more than two children */ #include<stdio.h> #include<conio.h> #include<iostream> using namespace std; struct BTreeNode { int *data; BTreeNode **child_ptr; bool leaf; int n; }*root = NULL, *np = NULL, *x = NULL; BTreeNode * init() { int i; np = new BTreeNode; np->data = new int[5]; np->child_ptr = new BTreeNode *[6]; np->leaf = true; np->n = 0; for (i = 0; i < 6; i++) { np->child_ptr[i] = NULL; } return np; } void traverse(BTreeNode *p) { cout<<endl; int i; for (i = 0; i < p->n; i++) { if (p->leaf == false) { traverse(p->child_ptr[i]); } cout << " " << p->data[i]; } if (p->leaf == false) { traverse(p->child_ptr[i]); } cout<<endl; } void sort(int *p, int n) { int i, j, temp; for (i = 0; i < n; i++) { for (j = i; j <= n; j++) { if (p[i] > p[j]) { temp = p[i]; p[i] = p[j]; p[j] = temp; } } } } int split_child(BTreeNode *x, int i) { int j, mid; BTreeNode *np1, *np3, *y; np3 = init(); np3->leaf = true; if (i == -1) { mid = x->data[2]; x->data[2] = 0; x->n--; np1 = init(); np1->leaf = false; x->leaf = true; for (j = 3; j < 5; j++) { np3->data[j - 3] = x->data[j]; np3->child_ptr[j - 3] = x->child_ptr[j]; np3->n++; x->data[j] = 0; x->n--; } for (j = 0; j < 6; j++) { x->child_ptr[j] = NULL; } np1->data[0] = mid; np1->child_ptr[np1->n] = x; np1->child_ptr[np1->n + 1] = np3; np1->n++; root = np1; } else { y = x->child_ptr[i]; mid = y->data[2]; y->data[2] = 0; y->n--; for (j = 3; j < 5; j++) { np3->data[j - 3] = y->data[j]; np3->n++; y->data[j] = 0; y->n--; } x->child_ptr[i + 1] = y; x->child_ptr[i + 1] = np3; } return mid; } void insert(int a) { int i, temp; x = root; if (x == NULL) { root = init(); x = root; } else { if (x->leaf == true && x->n == 5) { temp = split_child(x, -1); x = root; for (i = 0; i < (x->n); i++) { if ((a > x->data[i]) && (a < x->data[i + 1])) { i++; break; } else if (a < x->data[0]) { break; } else { continue; } } x = x->child_ptr[i]; } else { while (x->leaf == false) { for (i = 0; i < (x->n); i++) { if ((a > x->data[i]) && (a < x->data[i + 1])) { i++; break; } else if (a < x->data[0]) { break; } else { continue; } } if ((x->child_ptr[i])->n == 5) { temp = split_child(x, i); x->data[x->n] = temp; x->n++; continue; } else { x = x->child_ptr[i]; } } } } x->data[x->n] = a; sort(x->data, x->n); x->n++; } int main() { int i, n, t; cout<<"enter the no of elements to be inserted\n"; cin>>n; for(i = 0; i < n; i++) { cout<<"enter the element\n"; cin>>t; insert(t); } cout<<"traversal of constructed tree\n"; traverse(root); getch(); }

The if...else statement executes two different codes depending upon whether the test expression is true or false. Sometimes, a choice has to be made from more than 2 possibilities. The if...else ladder allows you to check between multiple test expressions and execute different statements. In C/C++ if-else-if ladder helps user decide from among multiple options. The C/C++ if statements are executed from the top down. As soon as one of the conditions controlling the if is true, the statement associated with that if is executed, and the rest of the C else-if ladder is bypassed. If none of the conditions is true, then the final else statement will be executed.

The cout is a predefined object of ostream class. It is connected with the standard output device, which is usually a display screen. The cout is used in conjunction with stream insertion operator (<<) to display the output on a console. On most program environments, the standard output by default is the screen, and the C++ stream object defined to access it is cout. The "c" in cout refers to "character" and "out" means "output". Hence cout means "character output". The cout object is used along with the insertion operator << in order to display a stream of characters.

Continue statement is used inside loops. Whenever a continue statement is encountered inside a loop, control directly jumps to the beginning of the loop for next iteration, skipping the execution of statements inside loop's body for the current iteration. The continue statement works somewhat like the break statement. Instead of forcing termination, however, continue forces the next iteration of the loop to take place, skipping any code in between. For the for loop, continue causes the conditional test and increment portions of the loop to execute. For the while and do...while loops, program control passes to the conditional tests.

The getch() is a predefined non-standard function that is defined in conio.h header file. It is mostly used by the Dev C/C++, MS- DOS's compilers like Turbo C to hold the screen until the user passes a single value to exit from the console screen. It can also be used to read a single byte character or string from the keyboard and then print. It does not hold any parameters. It has no buffer area to store the input character in a program. The getch() function does not accept any parameter from the user. It returns the ASCII value of the key pressed by the user as an input.

In computer programming, we use the if statement to run a block code only when a certain condition is met. An if statement can be followed by an optional else statement, which executes when the boolean expression is false. There are three forms of if...else statements in C++: • if statement, • if...else statement, • if...else if...else statement, The if statement evaluates the condition inside the parentheses ( ). If the condition evaluates to true, the code inside the body of if is executed. If the condition evaluates to false, the code inside the body of if is skipped.

Logical Operators are used to compare and connect two or more expressions or variables, such that the value of the expression is completely dependent on the original expression or value or variable. We use logical operators to check whether an expression is true or false. If the expression is true, it returns 1 whereas if the expression is false, it returns 0. Assume variable A holds 1 and variable B holds 0:

#include is a way of including a standard or user-defined file in the program and is mostly written at the beginning of any C/C++ program. This directive is read by the preprocessor and orders it to insert the content of a user-defined or system header file into the following program. These files are mainly imported from an outside source into the current program. The process of importing such files that might be system-defined or user-defined is known as File Inclusion. This type of preprocessor directive tells the compiler to include a file in the source code program.

In computer programming, loops are used to repeat a block of code. For example, when you are displaying number from 1 to 100 you may want set the value of a variable to 1 and display it 100 times, increasing its value by 1 on each loop iteration. When you know exactly how many times you want to loop through a block of code, use the for loop instead of a while loop. A for loop is a repetition control structure that allows you to efficiently write a loop that needs to execute a specific number of times.

A program shall contain a global function named main, which is the designated start of the program in hosted environment. main() function is the entry point of any C++ program. It is the point at which execution of program is started. When a C++ program is executed, the execution control goes directly to the main() function. Every C++ program have a main() function.

In C++, classes and structs are blueprints that are used to create the instance of a class. Structs are used for lightweight objects such as Rectangle, color, Point, etc. Unlike class, structs in C++ are value type than reference type. It is useful if you have data that is not intended to be modified after creation of struct. C++ Structure is a collection of different data types. It is similar to the class that holds different types of data. A structure is declared by preceding the struct keyword followed by the identifier(structure name). Inside the curly braces, we can declare the member variables of different types.

Break statement in C++ is a loop control statement defined using the break keyword. It is used to stop the current execution and proceed with the next one. When a compiler calls the break statement, it immediately stops the execution of the loop and transfers the control outside the loop and executes the other statements. In the case of a nested loop, break the statement stops the execution of the inner loop and proceeds with the outer loop. The statement itself says it breaks the loop. When the break statement is called in the program, it immediately terminates the loop and transfers the flow control to the statement mentioned outside the loop.

The cin object is used to accept input from the standard input device i.e. keyboard. It is defined in the iostream header file. C++ cin statement is the instance of the class istream and is used to read input from the standard input device which is usually a keyboard. The extraction operator(>>) is used along with the object cin for reading inputs. The extraction operator extracts the data from the object cin which is entered using the keyboard. The "c" in cin refers to "character" and "in" means "input". Hence cin means "character input". The cin object is used along with the extraction operator >> in order to receive a stream of characters.

Consider a situation, when we have two persons with the same name, jhon, in the same class. Whenever we need to differentiate them definitely we would have to use some additional information along with their name, like either the area, if they live in different area or their mother's or father's name, etc. Same situation can arise in your C++ applications. For example, you might be writing some code that has a function called xyz() and there is another library available which is also having same function xyz(). Now the compiler has no way of knowing which version of xyz() function you are referring to within your code.

A predefined object of the class called iostream class is used to insert the new line characters while flushing the stream is called endl in C++. This endl is similar to \n which performs the functionality of inserting new line characters but it does not flush the stream whereas endl does the job of inserting the new line characters while flushing the stream. Hence the statement cout<<endl; will be equal to the statement cout<< '\n' << flush; meaning the new line character used along with flush explicitly becomes equivalent to the endl statement in C++.

C supports nesting of loops in C. Nesting of loops is the feature in C that allows the looping of statements inside another loop. Any number of loops can be defined inside another loop, i.e., there is no restriction for defining any number of loops. The nesting level can be defined at n times. You can define any type of loop inside another loop; for example, you can define 'while' loop inside a 'for' loop. A loop inside another loop is called a nested loop. The depth of nested loop depends on the complexity of a problem. We can have any number of nested loops as required. Consider a nested loop where the outer loop runs n times and consists of another loop inside it. The inner loop runs m times. Then, the total number of times the inner loop runs during the program execution is n*m.

In while loop, condition is evaluated first and if it returns true then the statements inside while loop execute, this happens repeatedly until the condition returns false. When condition returns false, the control comes out of loop and jumps to the next statement in the program after while loop. The important point to note when using while loop is that we need to use increment or decrement statement inside while loop so that the loop variable gets changed on each iteration, and at some point condition returns false. This way we can end the execution of while loop otherwise the loop would execute indefinitely. A while loop that never stops is said to be the infinite while loop, when we give the condition in such a way so that it never returns false, then the loops becomes infinite and repeats itself indefinitely.

Allocate storage space. Default allocation functions (single-object form). A new operator is used to create the object while a delete operator is used to delete the object. When the object is created by using the new operator, then the object will exist until we explicitly use the delete operator to delete the object. Therefore, we can say that the lifetime of the object is not related to the block structure of the program.






A simple c++ program which shows using of switch statement in c++. C++ Program which takes input a grade and display Grade Points Average GPA. Program takes inputs A,a, B,b,


To "delete files" in C++, enter the file name to delete the file using the function remove(). If the file would be deleted successfully, then it ("remove()") will return 0 otherwise it will not


Sort array of points according to X coordinate and Y coordinate. Find the distance between two points. And return the 'smallest distance' between 2 points. Find the 'distance' beween