C++ Programming Code Examples
C++ > Mathematics Code Examples
Square Root in C++ programming
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/* Square Root in C++ programming
To get the square root of a double value use sqrt(double) function: */
cout << "The square root of 16 is " << sqrt(16.0) << endl;
cout << "The square root of 4 is " << sqrt(4.0) << endl;
cout << "The square root of 64 is " << sqrt(64.0) << endl;
cout << "Happy Codings  C++ Programming Language Code Examples";
sqrt() Function in C++
Compute square root. Returns the square root of x. The sqrt() function in C++ returns the square root of a number. This function is defined in the cmath header file. There are various functions available in the C++ Library to calculate the square root of a number. Most prominently, sqrt is used. It takes double as an argument. The <cmath> header defines two more inbuilt functions for calculating the square root of a number (apart from sqrt) which has an argument of type float and long double. Therefore, all the functions used for calculating square root in C++ are.
Mathematically, sqrt(x) = √x.
Additional overloads are provided in this header (<cmath>) for the integral types: These overloads effectively cast x to a double before calculations (defined for T being any integral type). This function is also overloaded in <complex> and <valarray> (see complex sqrt and valarray sqrt).
Syntax for sqrt() Function in C++
#include <cmath>
double sqrt (double x);
float sqrt (float x);
long double sqrt (long double x);
double sqrt (T x); // additional overloads for integral types
x
Value whose square root is computed. If the argument is negative, a domain error occurs.
The sqrt() function takes the following parameter:
x  a nonnegative number whose square root is to be computed.
The sqrt() function returns the square root of the given argument
If a negative argument is passed to sqrt(), domain error occurs.
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/* compute square root by sqrt() math function code example */
// C++ code to demonstrate the example of sqrt() function
#include <iostream>
#include <cmath>
using namespace std;
// main code section
int main()
{
float x;
//input the value
cout<<"Enter a number: ";
cin>>x;
// calculate the square root
float result = sqrt(x);
cout<<"square root of "<<x<<" is = "<<result;
cout<<endl;
return 0;
}
Arithmetic Operators in C++
Arithmetic Operator is used to performing mathematical operations such as addition, subtraction, multiplication, division, modulus, etc., on the given operands. For example: 6 + 3 = 9, 5  3 = 2, 3 * 4 = 12, etc. are the examples of arithmetic operators. Let's discuss the different types of Arithmetic Operators in the C programming.
+
Plus Operator is a simple Plus (+) Operator used to add two given operands. We can use Plus Operator with different data types such as integer, float, long, double, enumerated and string type data to add the given operand.

The minus operator is denoted by the minus () symbol. It is used to return the subtraction of the first number from the second number. The data type of the given number can be different types, such as int, float, double, long double, etc., in the programing language.
*
The multiplication operator is represented as an asterisk (*) symbol, and it is used to return the product of n1 and n2 numbers. The data type of the given number can be different types such as int, float, and double in the C programing language.
/
The division operator is an arithmetic operator that divides the first (n1) by the second (n2) number. Using division operator (/), we can divide the int, float, double and long data types variables.
%
The modulus operator is represented by the percentage sign (%), and it is used to return the remainder by dividing the first number by the second number.
++
Increment Operator is the type of Arithmetic operator, which is denoted by double plus (++) operator. It is used to increase the integer value by 1.

Decrement Operator is denoted by the double minus () symbol, which decreases the operand value by 1.
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/* Perhaps you have warm memories of doing arithmetic drills in grade school. You can give that same pleasure to your computer. C++ uses operators to do arithmetic. It provides operators for five basic arithmetic calculations: addition, subtraction, multiplication, division, and taking the modulus. Each of these operators uses two values (called operands) to calculate a final answer. Together, the operator and its operands constitute an expression. */
#include <iostream>
using namespace std;
int main() {
int a, b;
a = 7;
b = 2;
// printing the sum of a and b
cout << "a + b = " << (a + b) << endl;
// printing the difference of a and b
cout << "a  b = " << (a  b) << endl;
// printing the product of a and b
cout << "a * b = " << (a * b) << endl;
// printing the division of a by b
cout << "a / b = " << (a / b) << endl;
// printing the modulo of a by b
cout << "a % b = " << (a % b) << endl;
return 0;
}
Standard Output Stream (cout) in C++
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.
Syntax for cout in C++
cout << var_name;
//or
cout << "Some String";
<<
is the insertion operator
var_name
is usually a variable, but can also be an array element or elements of containers like vectors, lists, maps, etc.
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.
The << operator can be used more than once with a combination of variables, strings, and manipulators.
cout is used for displaying data on the screen. The operator << called as insertion operator or put to operator. The Insertion operator can be overloaded. Insertion operator is similar to the printf() operation in C. cout is the object of ostream class. Data flow direction is from variable to output device. Multiple outputs can be displayed using cout.
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/* standard output stream (cout) in C++ language */
#include <iostream>
using namespace std;
int main() {
string str = "Do not interrupt me";
char ch = 'm';
// use cout with write()
cout.write(str,6);
cout << endl;
// use cout with put()
cout.put(ch);
return 0;
}
Comments in C++
The C++ comments are statements that are not executed by the compiler. The comments in C++ programming can be used to provide explanation of the code, variable, method or class. If we write comments on our code, it will be easier for us to understand the code in the future. Also, it will be easier for your fellow developers to understand the code. By the help of comments, you can hide the program code also. There are two types of comments in C++:
• Single Line comment
• Multi Line comment
Syntax for Single Line Comment in C++
/* This is a comment */
Syntax for Multi Line Comment in C++
/* C++ comments can also
* span multiple lines
*/
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/* program to illustrate use comments in C++ language */
#include <ostream>
using namespace std;
int main()
{
int x = 11; // x is a variable
cout<<x<<"\n";
/* declare and
print variable in C++ */
int x = 35;
cout<<x<<"\n";
// This is a comment
cout << "Hello World!";
/* Multiline Comments
in C++ */
}
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