 # C Program To Convert Octal to Decimal

C program to convert octal numbers to decimal numbers; Through this tutorial, we will learn how to convert octal numbers to decimal numbers in c programs with the help of functions.

## Algorithm to Convert Octal to Decimal

Use the following algorithm to write a program to convert octal numbers to decimal numbers; as follows:

• Take an input octal number from user and stored in an int type variable say octal.
• Create A function, which name convert().
1. Digits of octal are extracted one by one starting from right.

int rem = octal%10;

2. Extracted digits are multiplied with proper base i.e. power of 8.

int res = rem*pow(8,i);

3. After multiplying each digit with proper base the results are added and stored in another variable say decimal.

decimal += res;

• Call Convert function with parameters.
• The output is printed.

## C Program To Convert Octal to Decimal

```    #include <stdio.h>

// Function to convert octal number to decimal

int convert(int octal)

{

int decimal = 0, i = 0;

//converting octal to decimal

while (octal != 0)

{

int rem = octal % 10;

octal /= 10;

int res=rem*pow(8,i);

decimal += res;

i++;

}

return decimal;

}

//main program

int main()

{

int octal;

printf("Enter an octal number: ");

//user input

scanf("%d", &octal);

//calling function

int decimal=convert(octal);

//printing output

printf( " %d in octal = %d in decimal", octal, decimal);

return 0;

}
```

The output of the above c program; as follows:

`Enter an octal number: 120255120255 in octal = 41133 in decimal`

## Recommended C Programs 