# C++ Program to Generate Random Hexadecimal Bytes

C++Server Side ProgrammingProgramming

We shall discuss about a C++ program which can generate random Hexadecimal numbers. Here we shall use rand() and itoa() functions to implement the same. Let us discuss on these functions separately and categorically.

rand(): rand() function is a predefined method of C++. It is declared in <stdlib.h> header file. rand() is used to generate random number within a range. Here min_n is the minimum range of the random numbers and max_n is the maximum range of the numbers. So rand() will return the random numbers between min_n to (max_n – 1) inclusive of the limit values. Here if we mention lower and upper limits as 1 and 100 respectively, then rand() will return values from 1 to (100 – 1). i.e. from 1 to 99.

itoa(): It returns the converted value of a decimal or integer number. It converts the value to a null-terminated string with a specified base. It stores the converted value to a user defined array.

## Syntax

itoa(new_n, Hexadec_n, 16);

Here new_n is any random integer number and Hexadec_n is the user defined array and 16 is the base of hexadecimal number. That means in converts a decimal or integer number to hexadecimal number.

## Algorithm

Begin
Declare max_n to the integer datatype.
Initialize max_n = 100.
Declare min_n to the integer datatype.
Initialize min_n = 1.
Declare an array Hexadec_n to the character datatype.
Declare new_n to the integer datatype.
Declare i to the integer datatype.
for (i = 0; i < 5; i++)
new_n = ((rand() % (max_n + 1 - min_n)) + min_n)
Print “The random number is:”.
Print the value of new_n.
Call itoa(new_n, Hexadec_n, 16) method to
convert a random decimal number to hexadecimal number.
Print “Equivalent Hex Byte:”
End.

## Example

#include<iostream>
#include<conio.h>
#include<stdlib.h>
using namespace std;
int main(int argc, char **argv) {
int max_n = 100;
int min_n = 1;
int new_n;
int i;
for (i = 0; i < 5; i++) {
new_n = ((rand() % (max_n + 1 - min_n)) + min_n);
//rand() returns random decimal number.
cout<<"The random number is: "<<new_n;
cout << "\nEquivalent Hex Byte: "
}
return 0;
}

## Output

The random number is: 42
Equivalent Hex Byte: 2a
The random number is: 68
Equivalent Hex Byte: 44
The random number is: 35
Equivalent Hex Byte: 23
The random number is: 1
Equivalent Hex Byte: 1
The random number is: 70
Equivalent Hex Byte: 46