# Generate N Random Hexadecimal Numbers

• Last Updated : 02 Dec, 2021

Given a positive integer N, the task is to generate N random hexadecimal integers.

Examples:

Input: N = 3
Output:
E19B24CD01
A5E

Approach: The given problem can be solved with the help of the rand() function which is used to generate random integers. A character array can be created which stores all the possible characters in the hexadecimal notation and randomly select the characters from the array.

Below is the implementation of the above approach:

## C++

 `// C++ program for the above approach` `#include ``using` `namespace` `std;` `// Maximum length of the random integer``const` `int` `maxSize = 10;` `// Function to generate N Hexadecimal``// integers``void` `randomHexInt(``int` `N)``{``    ``srand``(``time``(0));` `    ``// Stores all the possible characters``    ``// in the Hexadecimal notation``    ``char` `hexChar[]``        ``= { ``'0'``, ``'1'``, ``'2'``, ``'3'``, ``'4'``, ``'5'``,``            ``'6'``, ``'7'``, ``'8'``, ``'9'``, ``'A'``, ``'B'``,``            ``'C'``, ``'D'``, ``'E'``, ``'F'` `};` `    ``// Loop to print N integers``    ``for` `(``int` `i = 0; i < N; i++) {` `        ``// Randomly select length of the``        ``// int in the range [1, maxSize]``        ``int` `len = ``rand``() % maxSize + 1;` `        ``// Print len characters``        ``for` `(``int` `j = 0; j < len; j++) {` `            ``// Print a randomly selected``            ``// character``            ``cout << hexChar[``rand``() % 16];``        ``}``        ``cout << ``'\n'``;``    ``}``}` `// Driver Code``int` `main()``{``    ``int` `N = 3;``    ``randomHexInt(N);` `    ``return` `0;``}`

## Java

 `// Java program for the above approach``class` `GFG{``    ` `// Maximum length of the random integer``static` `int` `maxSize = ``10``;` `// Function to generate N Hexadecimal``// integers``static` `void` `randomHexInt(``int` `N)``{``    ` `    ``// Stores all the possible characters``    ``// in the Hexadecimal notation``    ``char` `hexChar[]``        ``= { ``'0'``, ``'1'``, ``'2'``, ``'3'``, ``'4'``, ``'5'``,``            ``'6'``, ``'7'``, ``'8'``, ``'9'``, ``'A'``, ``'B'``,``            ``'C'``, ``'D'``, ``'E'``, ``'F'` `};` `    ``// Loop to print N integers``    ``for` `(``int` `i = ``0``; i < N; i++) {` `        ``// Randomly select length of the``        ``// int in the range [1, maxSize]``        ``int` `len = (``1` `+ (``int``)(Math.random() * ``100``)) % maxSize + ``1``;` `        ``// Print len characters``        ``for` `(``int` `j = ``0``; j < len; j++) {` `            ``// Print a randomly selected``            ``// character``            ``System.out.print(hexChar[(``1` `+ (``int``)(Math.random() * ``100``)) % ``16``]);``        ``}``        ``System.out.println();``    ``}``}`  `// Driver Code``public` `static` `void` `main (String[] args)``{``    ``int` `N = ``3``;``    ``randomHexInt(N);``}``}` `// This code is contributed by sanjoy_62.`

## Python3

 `# Python3 program for the above approach``import` `random,math` `# Maximum length of the random integer``maxSize ``=` `10``;` `# Function to generate N Hexadecimal``# integers``def` `randomHexInt(N) :` `    ``# Stores all the possible characters``    ``# in the Hexadecimal notation``    ``hexChar ``=` `[ ``'0'``, ``'1'``, ``'2'``, ``'3'``, ``'4'``, ``'5'``,``            ``'6'``, ``'7'``, ``'8'``, ``'9'``, ``'A'``, ``'B'``,``            ``'C'``, ``'D'``, ``'E'``, ``'F'``];` `    ``# Loop to print N integers``    ``for` `i ``in` `range``(N) :` `        ``# Randomly select length of the``        ``# int in the range [1, maxSize]``        ``Len` `=` `math.floor(random.random() ``*` `(maxSize ``-` `1``) ``+` `1``)` `        ``# Print len characters``        ``for` `j ``in` `range``(``Len``) :` `            ``# Print a randomly selected``            ``# character``            ``print``(hexChar[math.floor(random.random() ``*` `16``)],end ``=` `"");` `        ``print``();` `# Driver Code``if` `__name__ ``=``=` `"__main__"` `:` `    ``N ``=` `3``;``    ``randomHexInt(N);` `    ``# This code is contributed by AnkThon`

## C#

 `// C# program for the above approach``using` `System;``using` `System.Collections.Generic;``using` `System.Linq;` `public` `class` `GFG {``    ` `// Maximum length of the random integer``static` `int` `maxSize = 10;` `// Function to generate N Hexadecimal``// integers``static` `void` `randomHexInt(``int` `N)``{``    ` `    ``// Stores all the possible characters``    ``// in the Hexadecimal notation``    ``char``[] hexChar``        ``= { ``'0'``, ``'1'``, ``'2'``, ``'3'``, ``'4'``, ``'5'``,``            ``'6'``, ``'7'``, ``'8'``, ``'9'``, ``'A'``, ``'B'``,``            ``'C'``, ``'D'``, ``'E'``, ``'F'` `};``            ` `    ``// For random generator``    ``Random rand = ``new` `Random();` `    ``// Loop to print N integers``    ``for` `(``int` `i = 0; i < N; i++) {` `        ``// Randomly select length of the``        ``// int in the range [1, maxSize]``        ``int` `len = rand.Next() % maxSize + 1;` `        ``// Print len characters``        ``for` `(``int` `j = 0; j < len; j++) {` `            ``// Print a randomly selected``            ``// character``            ``Console.Write(hexChar[rand.Next() % 16]);``        ``}``        ``Console.WriteLine();``    ``}``}` `// Driver Code``public` `static` `void` `Main (``string``[] args) {``    ` `    ``int` `N = 3;``    ``randomHexInt(N);``}``}` `// This code is contributed by code_hunt.`

## Javascript

 ``
Output:
```B71C3
EC3BBC90
82410C0D```

Time Complexity: O(N*M) where M represents the maximum length of the random string.
Auxiliary Space: O(1)

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