Given a decimal number as input, we need to write a program to convert the given decimal number into equivalent hexadecimal number. i.e convert the number with base value 10 to base value 16.
Hexadecimal numbers use 16 values to represent a number. Numbers from 0-9 are expressed by digits 0-9 and 10-15 are represented by characters from A – F.
Examples:
Input : 116
Output: 74Input : 10
Output: AInput : 33
Output: 21
Algorithm:
- Store the remainder when the number is divided by 16 in a temporary variable temp. If temp is less than 10, insert (48 + temp) in a character array otherwise if temp is greater than or equals to 10, insert (55 + temp) in the character array.
- Divide the number by 16 now
- Repeat the above two steps until the number is not equal to 0.
- Print the array in reverse order now.
Example
If the given decimal number is 2545.
Step 1: Calculate remainder when 2545 is divided by 16 is 1. Therefore, temp = 1. As temp is less than 10. So, arr[0] = 48 + 1 = 49 = ‘1’.
Step 2: Divide 2545 by 16. New number is 2545/16 = 159.
Step 3: Calculate remainder when 159 is divided by 16 is 15. Therefore, temp = 15. As temp is greater than 10. So, arr[1] = 55 + 15 = 70 = ‘F’.
Step 4: Divide 159 by 16. New number is 159/16 = 9.
Step 5: Calculate remainder when 9 is divided by 16 is 9. Therefore, temp = 9. As temp is less than 10. So, arr[2] = 48 + 9 = 57 = ‘9’.
Step 6: Divide 9 by 16. New number is 9/16 = 0.
Step 7: Since number becomes = 0. Stop repeating steps and print the array in reverse order. Therefore, the equivalent hexadecimal number is 9F1.
Below diagram shows an example of converting the decimal number 2545 to an equivalent hexadecimal number.
Below is the implementation of the above idea.
C++
// C++ program to convert a decimal // number to hexadecimal number #include <iostream> using namespace std; // function to convert decimal to hexadecimal string decToHexa(int n) { // ans string to store hexadecimal number string ans = ""; while (n != 0) { // remainder variable to store remainder int rem = 0; // ch variable to store each character char ch; // storing remainder in rem variable. rem = n % 16; // check if temp < 10 if (rem < 10) { ch = rem + 48; } else { ch = rem + 55; } // updating the ans string with the character variable ans += ch; n = n / 16; } // reversing the ans string to get the final result int i = 0, j = ans.size() - 1; while(i <= j) { swap(ans[i], ans[j]); i++; j--; } return ans; } // Driver code int main() { int n = 2545; cout << decToHexa(n); return 0; } |
Java
// Java program to convert a decimal // number to hexadecimal number import java.io.*; class GFG { // function to convert decimal to hexadecimal static void decToHexa(int n) { // char array to store hexadecimal number char[] hexaDeciNum = new char[100]; // counter for hexadecimal number array int i = 0; while (n != 0) { // temporary variable to store remainder int temp = 0; // storing remainder in temp variable. temp = n % 16; // check if temp < 10 if (temp < 10) { hexaDeciNum[i] = (char)(temp + 48); i++; } else { hexaDeciNum[i] = (char)(temp + 55); i++; } n = n / 16; } // printing hexadecimal number array in reverse // order for (int j = i - 1; j >= 0; j--) System.out.print(hexaDeciNum[j]); } // driver program public static void main(String[] args) { int n = 2545; decToHexa(n); } } // Contributed by Pramod Kumar |
Python3
# Python3 program to # convert a decimal # number to hexadecimal # number # function to convert # decimal to hexadecimal def decToHexa(n): # char array to store # hexadecimal number hexaDeciNum = ['0'] * 100 # counter for hexadecimal # number array i = 0 while(n != 0): # temporary variable # to store remainder temp = 0 # storing remainder # in temp variable. temp = n % 16 # check if temp < 10 if(temp < 10): hexaDeciNum[i] = chr(temp + 48) i = i + 1 else: hexaDeciNum[i] = chr(temp + 55) i = i + 1 n = int(n / 16) # printing hexadecimal number # array in reverse order j = i - 1 while(j >= 0): print((hexaDeciNum[j]), end="") j = j - 1 # Driver Code n = 2545decToHexa(n) # This code is contributed # by mits. |
C#
// C# program to convert a decimal // number to hexadecimal number using System; class GFG { // function to convert decimal // to hexadecimal static void decToHexa(int n) { // char array to store // hexadecimal number char[] hexaDeciNum = new char[100]; // counter for hexadecimal number array int i = 0; while (n != 0) { // temporary variable to // store remainder int temp = 0; // storing remainder in temp // variable. temp = n % 16; // check if temp < 10 if (temp < 10) { hexaDeciNum[i] = (char)(temp + 48); i++; } else { hexaDeciNum[i] = (char)(temp + 55); i++; } n = n / 16; } // printing hexadecimal number // array in reverse order for (int j = i - 1; j >= 0; j--) Console.Write(hexaDeciNum[j]); } // Driver Code public static void Main(String[] args) { int n = 2545; decToHexa(n); } } // This code is contributed by Nitin Mittal. |
PHP
<?php // PHP program to convert // a decimal number to // hexadecimal number // function to convert // decimal to hexadecimal function decToHexa($n) { // char array to store // hexadecimal number $hexaDeciNum; // counter for hexadecimal // number array $i = 0; while($n != 0) { // temporary variable // to store remainder $temp = 0; // storing remainder // in temp variable. $temp = $n % 16; // check if temp < 10 if($temp < 10) { $hexaDeciNum[$i] = chr($temp + 48); $i++; } else { $hexaDeciNum[$i] = chr($temp + 55); $i++; } $n = (int)($n / 16); } // printing hexadecimal number // array in reverse order for($j = $i - 1; $j >= 0; $j--) echo $hexaDeciNum[$j]; } // Driver Code $n = 2545; decToHexa($n); // This code is contributed // by mits. ?> |
Javascript
<script> // Javascript program to convert a decimal // number to hexadecimal number // function to convert decimal to hexadecimal function decToHexa(n) { // char array to store hexadecimal number var hexaDeciNum = Array.from({length: 100}, (_, i) => 0); // counter for hexadecimal number array var i = 0; while (n != 0) { // temporary variable to store remainder var temp = 0; // storing remainder in temp variable. temp = n % 16; // check if temp < 10 if (temp < 10) { hexaDeciNum[i] = String.fromCharCode(temp + 48); i++; } else { hexaDeciNum[i] = String.fromCharCode(temp + 55); i++; } n = parseInt(n / 16); } // printing hexadecimal number array in reverse // order for (j = i - 1; j >= 0; j--) document.write(hexaDeciNum[j]); } // driver program var n = 2545; decToHexa(n); // This code contributed by shikhasingrajput </script> |
9F1
Time complexity: O(log16n)
Auxiliary space: O(1)
Using Predefined function
C++
// C++ program to convert decimal number to hexadecimal #include <iostream> using namespace std; // function to convert decimal number to hexadecimal void decToHexa(int n) { cout << hex << n << endl; } // driver code int main() { int n = 2545; decToHexa(n); return 0; } // This code is contributed by phasing17. |
Java
// Java program to convert a decimal // number to hexadecimal number import java.io.*; class GFG { public static void decToHexa(int n) { System.out.println(Integer.toHexString(n)); } public static void main(String[] args) { int n = 2545; decToHexa(n); } } |
Python3
# Python program to convert a decimal # number to hexadecimal number # function to convert decimal number # to equivalent hexadecimal number def decToHexa(n): return hex(n).replace("0x","") # Driver Code n = 2545print(decToHexa(n)) # This code is contributed by shahidedu7. |
C#
// C# program to convert a decimal // number to hexadecimal number using System; class GFG { public static void decToHexa(int n) { Console.Write(Convert.ToString(n)); } public static void Main(String[] args) { int n = 2545; decToHexa(n); } } // This code is contributed by shivanisinghss2110 |
Javascript
<script> // JS program to convert a decimal // number to hexadecimal number // Function to convert decimal to hexadecimal base integer function decToHexa(n) { document.write(n.toString(16)); } // Driver Code var n = 2545; decToHexa(n); // This code is contributed by phasing17 </script> |
9f1
Time Complexity: O(log16(n)), because we divide the n by 16 till it becomes zero.
Auxiliary Space: O(1), we cannot use any extra space.
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