*Write a C Program to Convert Octal to Decimal.*

Example,

Input: 245 Output: 165 Input: 472 Output: 314

If the input Octal Number is a char array, then we first convert char array to integer form.

In this article, we are taking the input Octal Number as integer.

## How to Convert from Octal to Decimal

Suppose you have a Octal Number,

The corresponding decimal number is given by

## Algorithm

#### Steps

Let **octal** be the input Octal Number

- Initialize
**p = 0, decimal = 0**. - Repeat the following steps while
.**octal**> 0- Set
**r =**.**octal**% 10 **octal****=**.**octal**/ 10**decimal = decimal + r * 8**^{p}**p = p + 1**.

- Set
- Return
**decimal**.

## Program to Convert Octal to Decimal in C

#include<stdio.h> #include<math.h> int OctalToDecimal(int n) { int p = 0, decimal = 0, r; while(n>0){ // retrieving the right-most digit of n r = n % 10; // dividing n by 10 to remove the // right-most digits since it is already // scanned in previous step n = n / 10; decimal = decimal + r * pow( 8 , p ); ++p; } return decimal; } int main() { int n, i, k; printf("Enter Octal: "); scanf("%d", &n); printf("\nDecimal of Octal Number %d is : %d", n, OctalToDecimal(n)); return 0; }

#### Output

*What to study next?*

## References

https://en.wikipedia.org/wiki/Octal