Given an octal number as input, we need to write a program to convert the given octal number into equivalent decimal number.
Examples:
Input : 67 Output : 55 Input : 512 Output : 330 Input: 123 Output: 83
The idea is to extract the digits of given octal number starting from right most digit and keep a variable dec_value. At the time of extracting digits from the octal number, multiply the digit with the proper base (Power of 8) and add it to the variable dec_value. At the end, the variable dec_value will store the required decimal number.
For Example:
If the octal number is 67.
dec_value = 6*(8^1) + 7*(8^0) = 55
Below diagram explains how to convert octal number ( 123 ) to equivalent decimal value:
Below is the implementation of above idea.
C/C++
// C++ program to convert octal to decimal #include <iostream> using namespace std; // Function to convert octal to decimal int octalToDecimal(int n) { int num = n; int dec_value = 0; // Initializing base value to 1, i.e 8^0 int base = 1; int temp = num; while (temp) { // Extracting last digit int last_digit = temp % 10; temp = temp / 10; // Multiplying last digit with appropriate // base value and adding it to dec_value dec_value += last_digit * base; base = base * 8; } return dec_value; } // Driver program to test above function int main() { int num = 67; cout << octalToDecimal(num) << endl; } |
Java
// Java program to convert octal to decimal import java.io.*; class GFG { // Function to convert octal to decimal static int octalToDecimal(int n) { int num = n; int dec_value = 0; // Initializing base value to 1, i.e 8^0 int base = 1; int temp = num; while (temp > 0) { // Extracting last digit int last_digit = temp % 10; temp = temp / 10; // Multiplying last digit with appropriate // base value and adding it to dec_value dec_value += last_digit * base; base = base * 8; } return dec_value; } // driver program public static void main(String[] args) { int num = 67; System.out.println(octalToDecimal(num)); } } // This code is contributed // by Pramod Kumar |
Python3
# Python3 program to convert # octal to decimal # Function to convert # octal to decimal def octalToDecimal(n): num = n; dec_value = 0; # Initializing base value # to 1, i.e 8^0 base = 1; temp = num; while (temp): # Extracting last digit last_digit = temp % 10; temp = int(temp / 10); # Multiplying last digit # with appropriate base # value and adding it # to dec_value dec_value += last_digit * base; base = base * 8; return dec_value; # Driver Code num = 67; print(octalToDecimal(num)); # This code is contributed by mits |
C#
// C# program to convert octal to // decimal using System; class GFG { // Function to convert octal // to decimal static int octalToDecimal(int n) { int num = n; int dec_value = 0; // Initializing base value // to 1, i.e 8^0 int b_ase = 1; int temp = num; while (temp > 0) { // Extracting last digit int last_digit = temp % 10; temp = temp / 10; // Multiplying last digit // with appropriate base // value and adding it to // dec_value dec_value += last_digit * b_ase; b_ase = b_ase * 8; } return dec_value; } // driver program public static void Main() { int num = 67; Console.WriteLine( octalToDecimal(num)); } } // This code is contributed by vt_m. |
PHP
<?php // PHP program to convert octal to decimal // Function to convert // octal to decimal function octalToDecimal($n) { $num = $n; $dec_value = 0; // Initializing base value // to 1, i.e 8^0 $base = 1; $temp = $num; while ($temp) { // Extracting last digit $last_digit = $temp % 10; $temp = $temp / 10; // Multiplying last digit // with appropriate base // value and adding it // to dec_value $dec_value += $last_digit * $base; $base = $base * 8; } return $dec_value; } // Driver Code $num = 67; echo octalToDecimal($num); // This code is contributed by anuj_67 ?> |
Output:
55
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