# C program to Convert Octal to Binary

Write a C program to convert octal to binary using a while loop. In this c example, the first while loop converts octal to decimal, and the second while loop converts a decimal to binary.

```#include <stdio.h>
#include <math.h>

int main()
{
int i, octal, decimal = 0;
long binary = 0;
i = 0;

printf("Enter the Octal Number = ");
scanf("%d",&octal);

while(octal != 0)
{
decimal = decimal + (octal % 10) * pow(8, i);
i++;
octal = octal / 10;
}
i = 1;
while(decimal != 0)
{
binary += ((decimal % 2) * i);
decimal = decimal / 2;
i = i * 10;
}

printf("The Binay Value = %ld\n", binary);
}```

In this c program, the octalToBinary function accepts the octal number and converts it to binary using the for loop.

```#include <stdio.h>
#include <math.h>

long octalToBinary(int octal)
{
int i, decimal = 0;
long binary = 0;
for (i = 0; octal != 0; i++)
{
decimal = decimal + (octal % 10) * pow(8, i);
octal = octal / 10;
}

for (i = 1; decimal != 0; i = i * 10)
{
binary = binary + (decimal % 2) * i;
decimal = decimal / 2;
}
return binary;
}

int main()
{
int octal;

printf("Enter the Number = ");
scanf("%d", &octal);

printf("Result = %ld\n", octalToBinary(octal));
}```
``````Enter the Number = 98
Result = 1010000

Enter the Number = 243
Result = 10100011``````