Garbage bits

Recalling Bennett s and Fredkin s trick to erase the garbage bits, the way in which the reversible logic circuit in figure 6.9 can be made to act as a real reversible serial-adder circuit is to first operate the circuit as shown, store the desired output, and then operate it backwards using the output and all intermediary garbage bits as new input. After all operations are completed in the reverse direction, we will be left with our desired answer stored on the side and with the serial-adder circuit back in its original state ready for another run. 

At this point your schematic may have bits of garbage floating around due to the editing. To get a fresh copy of the screen, select View and then Zoom from the menus ... 

Rural Militants bury illegal Items under metal scrap piles or where garbage with tin cans has been throvim for years. There is so much rust and bits of metal in the soil that the detector indicates that a tank is buried there. 

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