• 01-17-2002
ygfperson
i read somewhere that computers add using some combination of logic gates, and that the only way multiplication could be done is through addition. is this true, and if so, how?
• 01-17-2002
starX
think of multiplication like this:

9 multiplied by 8 means 9 eight times over,
so 9 * 8 == 9+9+9+9+9+9+9+9.

starX
www.axisoftime.com
• 01-18-2002
Deckard
I believe you're thinking of boolean logic gates. You may be interested in the explination provided here.
• 01-18-2002
ygfperson
about multiplication: what if the number were big? back when i had a tandy 1000ex(8.077 mhz, 1984 i think) basic could do a for i=1 to 5000, next loop in one second. is there some sort of help the processor gets?
• 01-18-2002
Salem
• 01-18-2002
iain
the multiplication cannot actually be done by a computer due to the logic systems it uses, so the multipolication is carried out by bit-shifting and addition
• 01-18-2002
QuestionC
Well, multiplication and loops are different beasts.

For multiplication: Technically, you could just have a multiplication table in your CPU, but the way I learned it, it's a combination of shifts, additions, and perhaps subtractions.

For loops: You can think of increment or decrement operators as even more basic than addition and subtraction. Loops are very important, so much that loop commands are commonly a part of a processor's architecture.
• 01-18-2002
sean
or you may be interested in wasting your time clicking the link provided here
• 01-19-2002
Deckard
Quote:

Originally posted by Sean
or you may be interested in wasting your time clicking the link provided here
That is a stroke of pure genius which should be prominently displayed at the beginning of the FAQ. :)