Lets Try For Decimal Integer Number how we add them
1 Add 759 + 674, but “forget” to carry I then get 323
2 Add 759 + 674 but only do the carrying, rather than the addition of
each digit I then
get 1110
3 Add the result of the first two operations (recursively, using the
same process de-
scribed in step 1 and 2): 1110 + 323 = 1433
we have done for decimal numbers
Now, how would we do this in binary?
1 If I add two binary numbers together but forget to carry, bit[i]
will be 0 if bit[i] in a and
b are both 0 or both 1 This is an XOR
2 If I add two numbers together but only carry, I will have a 1 in
bit[i] if bit[i-1] in a and b
are both 1’s This is an AND, shifted
3 Now, recurse until there’s nothing to carry
int add_no_arithm(int a, int b)
{
if (b == 0) return a;
int sum = a ^ b; // add without carrying
int carry = (a & b) << 1; // carry, but don’t add return
add_no_arithm(sum, carry); // recurse
}
Subtraction uses add function internally as well as we have adder !!!
int sub(int x, int y)
{
return(add(x,add(~y,1));
}
Thanks
Shashank Mani
Computer Science
Birla Institute of Technology Mesra
--
You received this message because you are subscribed to the Google Groups
"Algorithm Geeks" group.
To post to this group, send email to algogeeks@googlegroups.com.
To unsubscribe from this group, send email to
algogeeks+unsubscr...@googlegroups.com.
For more options, visit this group at
http://groups.google.com/group/algogeeks?hl=en.
