Octal To Binary Program In C

Implementation of this algorithm is given below −

#include <stdio.h>

int string_length(char s[])
{
	int i=0;

	while(s[i]!='\0')
		i++;
		
return i;	
}

void string_reverse(char s[])
{
  char *t;
	for(t=s+string_length(s)-1;s<t;++s,--t) {
		char temp=*s; *s=*t; *t=temp;
	}	
}

int binary2decimal(char n[])
{
	int i,decimal,mul=0;

	for(decimal=0,i=string_length(n)-1;i>=0;--i,++mul)
		decimal+=(n[i]-48)*(1<<mul);

	return decimal;
}

int main()
{   char n[10],bits[100];
	int i,j,d;
	
	printf("Enter a octal number : ");
	scanf("%s",n);

	string_reverse(n);
		
	for(i=j=0;n[i]!='\0';++i)
	  for(d=n[i]-48;d!=0;d/=2)
	  		bits[j++]=d%2+48;
	
	bits[j]='\0';

	string_reverse(bits);

	printf("Binary equivalent is : %s\n",bits);
return 0;
}

Output

Output of the program should be −

24 is even
31 is odd