Decimal, Hex, octal and binary number inter conversion

Introduction

The article discusses about all the number formats viz Binary, Decimal, Octal, Hex and BCD (Binary coded decimal) and conversion from Decimal to Binary, Octal and Hex and also the reverse conversion.

Binary

A numbering system based on 2 in which 0 and 1 are the only available digits.

Decimal

decimal fraction: a proper fraction whose denominator is a power of 10

Octal

A numbering system that uses eight digits, 0 through 7. It is used as a shorthand system for representing binary characters that use six bits.

Hexa Decimal

A numbering system which uses a base of 16. The first ten digits are 0-9 and the next six are A-F.

Binary to Decimal


void Bin2Dec()
{
int bin,n,r,s=0,i;
printf("Enter a binary number\n");
scanf("%d",&bin);
n=bin;
for(i=0;n!=0;i++)
{
r=n%10;
s=s+r*(int)pow(2,i);
n=n/10;
}
printf("The equivalent number of %d is %d\n",bin,s);
}

Octal to Decimal


void Oct2Dec()
{
int oct,n,r,s=0,i;
printf("Enter an octal number\n");
scanf("%d",&oct);
n=oct;
for(i=0;n!=0;i++)
{
r=n%10;
s=s+r*(int)pow(8,i);
n=n/10;
}
printf("The equivalent number of %d is %d\n",oct,s);
}

Hex to Decimal


void Hex2Dec()
{
char hex[N];
int i,j,n[N],l;
long double dec=0;
printf("Enter the hexa decimal number and find it's decimal equivalent\n");
fflush(stdin);
gets(hex);
l=strlen(hex);
for(i=0;i=0;j--)
{
printf("%d",bin[j]);
}
printf("\n");
}

Decimal to Octal


void Dec2Oct()
{
int n,r[10],i;
printf("Enter a number to find it's octal equivalent\n");
scanf("%d",&n);
printf("The octal equivalent of %d is ",n);
for(i=0;n!=0;i++)
{
r[i]=n%8;
n=n/8;
}
i--;
for(;i>=0;i--)
printf("%d",r[i]);
printf("\n");
}

Decimal to Hex


void Dec2Hex()
{
int n,r[10],i;
printf("Enter a number to get its hexadecimal equivalent\n");
scanf("%d",&n);
for(i=0;n!=0;i++)
{
r[i]=n%16;
n=n/16;
}
i--;
for(;i>=0;i--)
{
if(r[i]==10)
printf("A");
else if(r[i]==11)
printf("B");
else if(r[i]==12)
printf("C");
else if(r[i]==13)
printf("D");
else if(r[i]==14)
printf("E");
else if(r[i]==15)
printf("F");
else
printf("%d",r[i]);
}
printf("\n");
}